diff --git a/doc/chat_call_arch.md b/doc/chat_call_arch.md
index fc5f83ff..0101a64e 100644
--- a/doc/chat_call_arch.md
+++ b/doc/chat_call_arch.md
@@ -52,6 +52,13 @@ Autotools-сборка демона остаётся C-only (`.cpp` не ком
 присутствует и в демоне, аудиопроцессинг — только там, где есть GUI.
 
 Диагностика: категория `call` (`DEBUG_CATEGORY_CALL`); транспортная доставка — `etcp_route`.
+Desktop направляет сообщения FFmpeg и Qt в общий `debug_file` (по умолчанию `chatgui.log`).
+Начальная проверка codec пишет краткий итог на info, детали и ожидаемые отказы — на debug:
+`[gui] debug_categories=call=debug,video=debug`. Повторы FFmpeg внутри пробы сворачиваются со счётчиком;
+рабочие ошибки параллельного звонка сохраняют error/warn. Информационный stderr libva отключён по умолчанию;
+для диагностики драйвера можно явно запустить с `LIBVA_MESSAGING_LEVEL=2`.
+Отсутствующая desktop-запись приложения создаётся в XDG data applications для регистрации в portal.
+
 
 ## 3. Протокол (сигналинг svc_id 0x36, первый байт payload = subcmd)
 
diff --git a/src/video/video.c b/src/video/video.c
index d226b39c..1411dab7 100644
--- a/src/video/video.c
+++ b/src/video/video.c
@@ -38,6 +38,34 @@ static void vc_active_set(int v)   { __atomic_store_n(&g_transcode_active, v, __
 int video_transcode_get_progress(void) { return vc_progress_get(); }
 int video_transcode_is_active(void)    { return vc_active_get(); }
 
+/* Пробы не меняют глобальный уровень: параллельные звонки сохраняют рабочие ошибки. */
+#ifdef _MSC_VER
+static __declspec(thread) struct { unsigned depth, repeated; char last[1024]; } g_codec_probe;
+#else
+static __thread struct { unsigned depth, repeated; char last[1024]; } g_codec_probe;
+#endif
+
+static void video_codec_probe_flush(void) {
+    if (g_codec_probe.repeated)
+        DEBUG_DEBUG(DEBUG_CATEGORY_VIDEO, "ffmpeg probe: repeated=%u message=%s", g_codec_probe.repeated, g_codec_probe.last);
+    g_codec_probe.repeated = 0;
+}
+
+void video_codec_probe_begin(void) {
+    video_ffmpeg_init();
+    ++g_codec_probe.depth;
+}
+
+void video_codec_probe_end(void) {
+    if (!g_codec_probe.depth) { DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "video codec probe end without begin"); return; }
+    if (--g_codec_probe.depth) return;
+    video_codec_probe_flush(); g_codec_probe.last[0] = '\0';
+}
+
+int video_codec_log_level(int level) {
+    return g_codec_probe.depth && level >= DEBUG_LEVEL_ERROR && level < DEBUG_LEVEL_DEBUG ? DEBUG_LEVEL_DEBUG : level;
+}
+
 #ifndef HAVE_FFMPEG
 
 /* ─── сборка без ffmpeg: стабы ─── */
@@ -92,6 +120,13 @@ static void video_av_log_cb(void* avcl, int level, const char* fmt, va_list vl)
     vsnprintf(buf, sizeof(buf), fmt, vl);
     size_t len = strlen(buf);
     while (len > 0 && (buf[len - 1] == '\n' || buf[len - 1] == '\r')) buf[--len] = '\0';
+    if (!len) return;
+    if (g_codec_probe.depth && level <= AV_LOG_WARNING) {
+        if (!strcmp(g_codec_probe.last, buf)) { ++g_codec_probe.repeated; return; }
+        video_codec_probe_flush(); snprintf(g_codec_probe.last, sizeof(g_codec_probe.last), "%s", buf);
+        DEBUG_DEBUG(DEBUG_CATEGORY_VIDEO, "ffmpeg probe source=%s level=%d: %s", avcl ? av_default_item_name(avcl) : "none", level, buf);
+        return;
+    }
     if (headers) {
         if (!strstr(buf, "Packet:") && !strstr(buf, "init_qp_minus26") && !strstr(buf, "slice_qp_delta")
             && !strstr(buf, "pic_width_in_luma_samples") && !strstr(buf, "pic_height_in_luma_samples")
diff --git a/src/video/video.h b/src/video/video.h
index ffcab504..999b8158 100644
--- a/src/video/video.h
+++ b/src/video/video.h
@@ -14,6 +14,13 @@ struct UASYNC;
  * trace категории debug включает AMF и заголовки HEVC. В сборке без FFmpeg ничего не делает. */
 void video_ffmpeg_init(void);
 
+/* Проба доступности codec: begin/end парные, вложенные, только для текущего потока.
+ * Ожидаемые отказы FFmpeg выводятся на debug с подсчётом повторов; рабочие потоки не затрагиваются. */
+void video_codec_probe_begin(void);
+void video_codec_probe_end(void);
+/* Возвращает debug вместо error/warn/info внутри пробы; level — DEBUG_LEVEL_* из debug_config.h. */
+int video_codec_log_level(int level);
+
 /* ── целевой профиль: H.264 в MP4, не более 720p / 2 Mbit ── */
 
 #define VIDEO_TARGET_MAX_WIDTH   1280
diff --git a/tools/chatgui/CMakeLists.txt b/tools/chatgui/CMakeLists.txt
index 00b60a4b..09b9ae24 100644
--- a/tools/chatgui/CMakeLists.txt
+++ b/tools/chatgui/CMakeLists.txt
@@ -144,6 +144,10 @@ target_link_libraries(chatgui_live_video PUBLIC ${QT_LIBS} utun PRIVATE ${FFMPEG
 target_include_directories(chatgui_live_video PRIVATE ${FFMPEG_INCLUDE_DIRS})
 if(FFMPEG_FOUND)
     target_compile_definitions(chatgui_live_video PRIVATE HAVE_FFMPEG)
+    add_executable(test_video_diagnostics tests/test_video_diagnostics.cpp src/gui_log.cpp)
+    target_include_directories(test_video_diagnostics PRIVATE ${FFMPEG_INCLUDE_DIRS})
+    target_link_libraries(test_video_diagnostics PRIVATE chatgui_live_video ${QT_TEST_LIB} ${FFMPEG_TARGET} ${FFMPEG_LIBRARIES})
+    add_test(NAME test_video_diagnostics COMMAND test_video_diagnostics)
     add_executable(test_video_frame_image tests/test_video_frame_image.cpp)
     target_compile_definitions(test_video_frame_image PRIVATE HAVE_FFMPEG)
     target_include_directories(test_video_frame_image PRIVATE ${FFMPEG_INCLUDE_DIRS})
@@ -266,6 +270,8 @@ set_target_properties(utun_voice PROPERTIES POSITION_INDEPENDENT_CODE ON)
 
 add_executable(vibechat WIN32
     src/main.cpp
+    src/desktop_integration.cpp
+    src/gui_log.cpp
     src/single_instance.cpp
     src/mainwindow.cpp
     src/channellist.cpp
@@ -377,6 +383,11 @@ add_custom_target(vibechat_licenses ALL
     COMMAND ${CMAKE_COMMAND} -E copy_if_different ${UTUN_LICENSE_FILES} "$<TARGET_FILE_DIR:vibechat>/licenses"
     COMMENT "Copying uTun license documents")
 install(FILES ${UTUN_LICENSE_FILES} DESTINATION share/licenses/utun)
+if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
+    add_executable(test_desktop_integration tests/test_desktop_integration.cpp src/desktop_integration.cpp)
+    target_link_libraries(test_desktop_integration PRIVATE ${QT_LIBS} ${QT_TEST_LIB} utun)
+    add_test(NAME test_desktop_integration COMMAND test_desktop_integration)
+endif()
 if(FFMPEG_FOUND)
     target_compile_definitions(vibechat PRIVATE HAVE_FFMPEG)
 endif()
diff --git a/tools/chatgui/src/call_video_decoder.cpp b/tools/chatgui/src/call_video_decoder.cpp
index 09adcfa7..e619df46 100644
--- a/tools/chatgui/src/call_video_decoder.cpp
+++ b/tools/chatgui/src/call_video_decoder.cpp
@@ -1,6 +1,6 @@
 #include "call_video_decoder.h"
 #include "video_frame_image.h"
-#include "debug_config.h"
+#include "video_codec_log.h"
 #include "../../../src/call/call_video_bitstream.h"
 #include "../../../src/call/call_video_playout.h"
 #include <QTransform>
@@ -43,16 +43,17 @@ struct CallVideoDecoder::Impl {
     static AVPixelFormat getFormat(AVCodecContext* codec, const AVPixelFormat* formats) {
         auto* self = static_cast<Impl*>(codec->opaque);
         for (const auto* p = formats; *p != AV_PIX_FMT_NONE; ++p) if (*p == self->pixel) return *p;
-        DEBUG_ERROR(DEBUG_CATEGORY_CALL, "video GPU decoder pixel format unavailable expected=%d", self->pixel);
+        CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_CALL, "video GPU decoder pixel format unavailable expected=%d", self->pixel);
         return AV_PIX_FMT_NONE;
     }
     int failed(const char* stage, int result) {
         error = QString("Video decoder %1: %2").arg(stage, ffError(result));
-        DEBUG_ERROR(DEBUG_CATEGORY_CALL, "video decoder failed stage=%s backend=%s pending=%zu generation=%llu result=%d error=%s",
+        CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_CALL, "video decoder failed stage=%s backend=%s pending=%zu generation=%llu result=%d error=%s",
             stage, gpu ? av_hwdevice_get_type_name(DeviceType) : "cpu", pending.size(),
             (unsigned long long)format.generation, result, qPrintable(error)); return -1;
     }
     bool open(const call_video_format& f) {
+        video_ffmpeg_init();
         format = f;
         const AVCodec* implementation = avcodec_find_decoder(f.codec == CALL_VIDEO_H265 ? AV_CODEC_ID_HEVC : AV_CODEC_ID_H264);
         codec = implementation ? avcodec_alloc_context3(implementation) : nullptr;
@@ -84,7 +85,8 @@ struct CallVideoDecoder::Impl {
         int result = avcodec_open2(codec, implementation, nullptr);
         if (result < 0) { failed("open", result); return false; }
         error.clear();
-        DEBUG_INFO(DEBUG_CATEGORY_CALL, "video decoder opened codec=%u name=%s backend=%s threads=%d thread_type=%d level=%u generation=%llu",
+        CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_CALL,
+            "video decoder opened codec=%u name=%s backend=%s threads=%d thread_type=%d level=%u generation=%llu",
             f.codec, implementation->name, gpu ? av_hwdevice_get_type_name(DeviceType) : "cpu", codec->thread_count,
             codec->active_thread_type, f.level, (unsigned long long)f.generation); return true;
     }
@@ -97,7 +99,7 @@ unsigned CallVideoDecoder::pipelineFrames() const { return m->pipeline; }
 bool CallVideoDecoder::hardware() const { return m->gpu; }
 QString CallVideoDecoder::error() const { return m->error; }
 void CallVideoDecoder::useSoftware() {
-    DEBUG_WARN(DEBUG_CATEGORY_CALL, "video decoder switching to CPU after device failure pending=%zu; next input must be KEY",
+    CODEC_LOG(DEBUG_LEVEL_WARN, DEBUG_CATEGORY_CALL, "video decoder switching to CPU after device failure pending=%zu; next input must be KEY",
         m->pending.size());
     close(); m->backend = Backend::SoftwareOnly;
 }
@@ -155,7 +157,7 @@ int CallVideoDecoder::submit(const call_video_frame& f) {
     m->pending.push_back(f); m->pending.back().data = nullptr;
     return 1;
 #else
-    Q_UNUSED(f); DEBUG_ERROR(DEBUG_CATEGORY_CALL, "video decoder unavailable: no FFmpeg"); return -1;
+    Q_UNUSED(f); CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_CALL, "video decoder unavailable: no FFmpeg"); return -1;
 #endif
 }
 
@@ -238,15 +240,16 @@ call_video_caps CallVideoDecoder::capabilities(const std::atomic<bool>* running)
     static bool initialized = false;
     auto cancelled = [running] {
         if (!running || running->load()) return false;
-        DEBUG_INFO(DEBUG_CATEGORY_CALL, "video decoder capability probe cancelled by stop"); return true;
+        CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_CALL, "video decoder capability probe cancelled by stop"); return true;
     };
     std::unique_lock<std::mutex> guard(lock, std::defer_lock);
     while (!guard.try_lock()) { if (cancelled()) return {}; QThread::usleep(1000); }
     if (initialized) {
-        DEBUG_INFO(DEBUG_CATEGORY_CALL, "video decoder capabilities cache hit wait_us=%lld",
+        CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_CALL, "video decoder capabilities cache hit wait_us=%lld",
             (long long)(call_video_playout_now_us() - started));
         return caps;
     }
+    VideoCodecProbe diagnostics;
     call_video_caps probed{};
     for (unsigned codec = 1; codec <= 2; ++codec) {
         call_video_limit limit{};
@@ -293,7 +296,7 @@ call_video_caps CallVideoDecoder::capabilities(const std::atomic<bool>* running)
                             if (valid && received < 8) QThread::usleep(1000);
                         }
                         valid = valid && received == 8 && outputBeforeEos;
-                        DEBUG_INFO(DEBUG_CATEGORY_CALL, "video decoder probe codec=%u profile=%u size=%ux%u fps=%u backend=%d "
+                        CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_CALL, "video decoder probe codec=%u profile=%u size=%ux%u fps=%u backend=%d "
                             "valid=%d inputs=%u outputs=%u pipeline=%u elapsed_us=%lld",
                             codec, profile, w, h, fps, int(backend), valid, sent, received, decoder.pipelineFrames(),
                             (long long)(call_video_playout_now_us() - start));
@@ -317,12 +320,18 @@ call_video_caps CallVideoDecoder::capabilities(const std::atomic<bool>* running)
               }
             }
         }
+        unsigned gpu = 0;
+#ifdef HAVE_FFMPEG
+        for (unsigned tier = 0; tier < 2; ++tier) for (unsigned rate = 0; rate < 3; ++rate)
+            gpu |= gpuProfiles[codec - 1][tier][rate].load();
+#endif
+        DEBUG_INFO(DEBUG_CATEGORY_CALL, "video decoder capabilities codec=%u available_profiles=%u gpu_profiles=%u", codec, limit.profiles, gpu);
         if (limit.profiles) {
             if (!call_video_limit_orientations(&limit, codec)) probed.decode[codec - 1] = limit;
         }
     }
     caps = probed; initialized = true;
-    DEBUG_INFO(DEBUG_CATEGORY_CALL, "video decoder capabilities verified elapsed_us=%lld",
+    CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_CALL, "video decoder capabilities verified elapsed_us=%lld",
         (long long)(call_video_playout_now_us() - started));
     return caps;
 }
diff --git a/tools/chatgui/src/call_video_encoder.cpp b/tools/chatgui/src/call_video_encoder.cpp
index b849c616..55cd740b 100644
--- a/tools/chatgui/src/call_video_encoder.cpp
+++ b/tools/chatgui/src/call_video_encoder.cpp
@@ -1,5 +1,5 @@
 #include "call_video_encoder.h"
-#include "debug_config.h"
+#include "video_codec_log.h"
 #include "../../../src/call/call_video_rate.h"
 #include "../../../src/call/call_video_bitstream.h"
 #include <QElapsedTimer>
@@ -9,7 +9,7 @@ bool CallVideoEncoder::open(const call_video_format& format, uint32_t bitrate, c
     if (!call_video_format_valid(&format) || bitrate < CALL_VIDEO_RATE_MIN_BPS || bitrate > format.maximum_bps
         || (format.codec == CALL_VIDEO_H265 && format.profile != CALL_VIDEO_MAIN)) {
         m_error = "Invalid call video encoder configuration";
-        DEBUG_ERROR(DEBUG_CATEGORY_CALL, "call video open invalid generation=%llu codec=%u level=%u bitrate=%u cap=%u profile=%u",
+        CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_CALL, "call video open invalid generation=%llu codec=%u level=%u bitrate=%u cap=%u profile=%u",
                     (unsigned long long)format.generation, format.codec, format.level, bitrate, format.maximum_bps, format.profile); return false;
     }
     LiveVideoConfig config;
@@ -19,10 +19,11 @@ bool CallVideoEncoder::open(const call_video_format& format, uint32_t bitrate, c
     config.profile = format.codec == CALL_VIDEO_H264 ? LiveVideoProfile::H264ConstrainedBaseline : LiveVideoProfile::H265Main;
     auto candidate = std::make_unique<LiveVideoEncoder>();
     if (!candidate->open(config, LiveVideoEncoder::Backend::Automatic)) {
-        m_error = candidate->error(); DEBUG_ERROR(DEBUG_CATEGORY_CALL, "call video open failed: %s", qPrintable(m_error)); return false;
+        m_error = candidate->error(); CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_CALL,
+            "call video open failed: %s", qPrintable(m_error)); return false;
     }
     close(); m_encoder = std::move(candidate); m_config = config; m_config.backend = m_encoder->name(); m_format = format;
-    DEBUG_INFO(DEBUG_CATEGORY_CALL, "call video encoder opened generation=%llu codec=%d encoder=%s bitrate=%d level=%d",
+    CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_CALL, "call video encoder opened generation=%llu codec=%d encoder=%s bitrate=%d level=%d",
                (unsigned long long)format.generation, config.codec, qPrintable(m_config.backend), config.bitrate, config.level); return true;
 }
 
diff --git a/tools/chatgui/src/call_video_engine.cpp b/tools/chatgui/src/call_video_engine.cpp
index d2f570fc..c0a5ef83 100644
--- a/tools/chatgui/src/call_video_engine.cpp
+++ b/tools/chatgui/src/call_video_engine.cpp
@@ -3,6 +3,7 @@
 #include "call_video_decoder.h"
 #include "call_video_wake.h"
 #include "call_video_queue.h"
+#include "video_codec_log.h"
 #include "call_camera_capture.h"
 #include "../../../src/call/call_video_port.h"
 #include "../../../src/call/call_video_playout.h"
@@ -270,6 +271,7 @@ call_video_caps CallVideoEngine::capabilities(const std::atomic<bool>* running)
         return verified;
     }
     DEBUG_INFO(DEBUG_CATEGORY_CALL, "video codec preparation begin; camera and network unused");
+    VideoCodecProbe diagnostics;
     call_video_caps caps = CallVideoDecoder::capabilities(running);
     // Не связываем приём с наличием собственного encoder.
     for (unsigned codec = 1; codec <= 2; ++codec) {
@@ -286,7 +288,7 @@ call_video_caps CallVideoEngine::capabilities(const std::atomic<bool>* running)
                 probe.width = portrait ? size.height() : size.width(); probe.height = portrait ? size.width() : size.height();
                 CallVideoEncoder encoder;
                 bothOrientations = encoder.open(probe, 1000000);
-                if (!bothOrientations) DEBUG_WARN(DEBUG_CATEGORY_CALL, "call codec probe unavailable codec=%u size=%ux%u: %s",
+                if (!bothOrientations) DEBUG_DEBUG(DEBUG_CATEGORY_CALL, "call codec probe unavailable codec=%u size=%ux%u: %s",
                     codec, probe.width, probe.height, qPrintable(encoder.error()));
             }
             if (bothOrientations) {
@@ -295,7 +297,7 @@ call_video_caps CallVideoEngine::capabilities(const std::atomic<bool>* running)
                 limit.fps = std::max<unsigned>(limit.fps, fps);
                 limit.pixels_per_second = std::max<unsigned>(limit.pixels_per_second, size.width() * size.height() * fps);
                 limit.maximum_bps = 4000000; limit.profiles = probe.profile; limit.level = std::max(limit.level, probe.level);
-                DEBUG_INFO(DEBUG_CATEGORY_CALL, "call encoder probe codec=%u size=%dx%d fps=%u level=%u verified=1",
+                DEBUG_DEBUG(DEBUG_CATEGORY_CALL, "call encoder probe codec=%u size=%dx%d fps=%u level=%u verified=1",
                     codec, size.width(), size.height(), fps, probe.level);
             }
           }
@@ -304,6 +306,10 @@ call_video_caps CallVideoEngine::capabilities(const std::atomic<bool>* running)
     }
     if (cancelled()) return {};
     verified = caps; initialized = true;
+    if (!caps.encode[0].profiles && !caps.encode[1].profiles)
+        DEBUG_WARN(DEBUG_CATEGORY_CALL, "video codec preparation: no usable encoder; details require call=debug,video=debug");
+    if (!caps.decode[0].profiles && !caps.decode[1].profiles)
+        DEBUG_WARN(DEBUG_CATEGORY_CALL, "video codec preparation: no usable decoder; details require call=debug,video=debug");
     DEBUG_INFO(DEBUG_CATEGORY_CALL, "video codec preparation complete elapsed_us=%lld encode=%u/%u decode=%u/%u",
         (long long)(nowUs() - started), caps.encode[0].profiles, caps.encode[1].profiles,
         caps.decode[0].profiles, caps.decode[1].profiles);
diff --git a/tools/chatgui/src/desktop_integration.cpp b/tools/chatgui/src/desktop_integration.cpp
new file mode 100644
index 00000000..7fef8037
--- /dev/null
+++ b/tools/chatgui/src/desktop_integration.cpp
@@ -0,0 +1,38 @@
+#include "desktop_integration.h"
+#include "debug_config.h"
+#include <QDir>
+#include <QSaveFile>
+#include <QStandardPaths>
+
+bool registerDesktopApplication(const QString& executable) {
+#ifdef Q_OS_LINUX
+    const QString relative = QStringLiteral("applications/org.utun.vibechat.desktop");
+    if (!QStandardPaths::locate(QStandardPaths::GenericDataLocation, relative).isEmpty()) return true;
+    const QString root = QStandardPaths::writableLocation(QStandardPaths::GenericDataLocation);
+    const QString path = root + '/' + relative;
+    if (root.isEmpty() || !QDir().mkpath(root + "/applications")) {
+        DEBUG_WARN(DEBUG_CATEGORY_GENERAL, "Desktop registration: cannot create applications directory in %s", qPrintable(root));
+        return false;
+    }
+    // Exec сначала разбирается как desktop string, затем как командная строка; shell не используется.
+    QString command;
+    for (QChar c : executable) {
+        if (c == '%') command += "%%";
+        else { if (c == '\\' || c == '"' || c == '$' || c == '`') command += '\\'; command += c; }
+    }
+    command = '"' + command + '"';
+    command.replace("\\", "\\\\"); command.replace('\n', "\\n"); command.replace('\r', "\\r"); command.replace('\t', "\\t");
+    // GLib проверяет executable до раскрытия %%; env оставляет путь аргументом и корректно обрабатывает '%' в имени.
+    const QByteArray content = QString("[Desktop Entry]\nType=Application\nName=VibeChat\nExec=/usr/bin/env %1\n"
+        "Icon=applications-internet\nTerminal=false\nCategories=Network;InstantMessaging;\n").arg(command).toUtf8();
+    QSaveFile file(path);
+    if (!file.open(QIODevice::WriteOnly) || file.write(content) != content.size() || !file.commit()) {
+        DEBUG_WARN(DEBUG_CATEGORY_GENERAL, "Desktop registration failed path=%s: %s", qPrintable(path), qPrintable(file.errorString()));
+        return false;
+    }
+    DEBUG_INFO(DEBUG_CATEGORY_GENERAL, "Desktop application registered path=%s", qPrintable(path));
+#else
+    Q_UNUSED(executable);
+#endif
+    return true;
+}
diff --git a/tools/chatgui/src/desktop_integration.h b/tools/chatgui/src/desktop_integration.h
new file mode 100644
index 00000000..c608d5d7
--- /dev/null
+++ b/tools/chatgui/src/desktop_integration.h
@@ -0,0 +1,8 @@
+// Linux: описание приложения для desktop portal при запуске переносимой/devel-сборки.
+#pragma once
+#include <QString>
+
+// Создаёт отсутствующий org.utun.vibechat.desktop в XDG data applications.
+// executable — абсолютный путь к GUI; готовые системные/user записи не заменяет.
+// Возвращает false с предупреждением в логе при ошибке записи; вне Linux возвращает true.
+bool registerDesktopApplication(const QString& executable);
diff --git a/tools/chatgui/src/gui_log.cpp b/tools/chatgui/src/gui_log.cpp
new file mode 100644
index 00000000..3537e112
--- /dev/null
+++ b/tools/chatgui/src/gui_log.cpp
@@ -0,0 +1,17 @@
+#include "gui_log.h"
+#include "debug_config.h"
+#include <QByteArray>
+#include <QString>
+#include <cstring>
+
+static void guiLog(QtMsgType type, const QMessageLogContext& context, const QString& message) {
+    const debug_level_t level = type == QtDebugMsg ? DEBUG_LEVEL_DEBUG : type == QtInfoMsg ? DEBUG_LEVEL_INFO
+        : type == QtWarningMsg ? DEBUG_LEVEL_WARN : DEBUG_LEVEL_ERROR;
+    const char* name = context.category ? context.category : "default";
+    const int category = !strncmp(name, "qt.multimedia", 13) ? DEBUG_CATEGORY_VIDEO : DEBUG_CATEGORY_GENERAL;
+    if (!debug_should_output(level, category)) return;
+    const auto text = message.toUtf8();
+    debug_output(level, category, context.function, context.file, context.line, "Qt[%s]: %s", name, text.constData());
+}
+
+QtMessageHandler installGuiLogHandler() { return qInstallMessageHandler(guiLog); }
diff --git a/tools/chatgui/src/gui_log.h b/tools/chatgui/src/gui_log.h
new file mode 100644
index 00000000..a793617b
--- /dev/null
+++ b/tools/chatgui/src/gui_log.h
@@ -0,0 +1,6 @@
+// Диагностика Qt через общий лог ядра: уровни/категории и debug_file применяются как к остальным сообщениям.
+#pragma once
+#include <QtGlobal>
+
+// Вызывать до создания QApplication; возвращает прежний Qt handler (для восстановления в тестах).
+QtMessageHandler installGuiLogHandler();
diff --git a/tools/chatgui/src/live_video_encoder.cpp b/tools/chatgui/src/live_video_encoder.cpp
index 8a170682..d2c222dd 100644
--- a/tools/chatgui/src/live_video_encoder.cpp
+++ b/tools/chatgui/src/live_video_encoder.cpp
@@ -1,5 +1,5 @@
 #include "live_video_encoder.h"
-#include "debug_config.h"
+#include "video_codec_log.h"
 #include <QElapsedTimer>
 #include <QPainter>
 #include <algorithm>
@@ -96,7 +96,7 @@ bool verifiedProfile(const LiveVideoConfig& config, const QList<LiveEncodedFrame
         uint16_t(config.rotation), uint8_t(config.codec), uint8_t(config.level), uint32_t(config.bitrate),
         uint8_t(config.codec == STREAM_MEDIA_H264 ? CALL_VIDEO_CONSTRAINED_BASELINE : CALL_VIDEO_MAIN)};
     if (call_video_check_key(&format, reinterpret_cast<const uint8_t*>(data.constData()), data.size())) {
-        DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "live call KEY verification failed codec=%d size=%dx%d level=%d bytes=%lld",
+        CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO, "live call KEY verification failed codec=%d size=%dx%d level=%d bytes=%lld",
             config.codec, config.width, config.height, config.level, (long long)data.size());
         return false;
     }
@@ -126,7 +126,7 @@ bool verifiedProfile(const LiveVideoConfig& config, const QList<LiveEncodedFrame
     bool valid = result >= 0 && idr && mainTier && decoder->profile == profile && decoder->level == config.level
         && !decoder->has_b_frames && decoded->format == AV_PIX_FMT_YUV420P
         && decoded->width == config.width && decoded->height == config.height;
-    if (!valid) DEBUG_ERROR(DEBUG_CATEGORY_VIDEO,
+    if (!valid) CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO,
         "live profile verification failed codec=%d result=%d idr=%d main_tier=%d profile=%d/%d level=%d/%d pixel=%d B=%d",
         config.codec, result, idr, mainTier, decoder ? decoder->profile : -1, profile,
         decoder ? decoder->level : -1, config.level, decoded ? decoded->format : -1, decoder ? decoder->has_b_frames : -1);
@@ -146,7 +146,8 @@ bool LiveVideoEncoder::open(const LiveVideoConfig& config, Backend backend) {
         || (constrained && (config.level <= 0 || config.level > 255 || config.references != 1 || !config.vbvBits
             || !((config.codec == 1 && config.profile == LiveVideoProfile::H264ConstrainedBaseline)
                 || (config.codec == 2 && config.profile == LiveVideoProfile::H265Main))))) {
-        m->error = "Invalid video configuration"; DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "desktop encoder invalid configuration"); return false;
+        m->error = "Invalid video configuration"; CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO,
+            "desktop encoder invalid configuration"); return false;
     }
 #ifdef HAVE_FFMPEG
     video_ffmpeg_init();
@@ -198,7 +199,7 @@ bool LiveVideoEncoder::open(const LiveVideoConfig& config, Backend backend) {
                 const int workers = 4;
                 QByteArray params = name == "libx264" ? "threads=4:sliced-threads=1:scenecut=0:open-gop=0:repeat-headers=0"
                     : "bframes=0:rc-lookahead=0:open-gop=0:frame-threads=1:wpp=1:log-level=error:pools=" + QByteArray::number(workers);
-                DEBUG_INFO(DEBUG_CATEGORY_VIDEO, "live CPU parallelism encoder=%s workers=%d mode=%s cpu_count=%d",
+                CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_VIDEO, "live CPU parallelism encoder=%s workers=%d mode=%s cpu_count=%d",
                     name.constData(), workers, name == "libx264" ? "sliced" : "wpp/frame-threads=1", av_cpu_count());
                 if (constrained) {
                     av_dict_set(&options, "profile", name == "libx264" ? "baseline" : "main", 0);
@@ -237,7 +238,7 @@ bool LiveVideoEncoder::open(const LiveVideoConfig& config, Backend backend) {
                     av_dict_set(&options, "profile", config.codec == STREAM_MEDIA_H264 ? "constrained_baseline" : "main", 0);
                     if (config.codec == STREAM_MEDIA_H265) av_dict_set(&options, "profile_tier", "main", 0);
                 }
-                DEBUG_INFO(DEBUG_CATEGORY_VIDEO,
+                CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_VIDEO,
                     "desktop AMF low latency settings name=%s usage=%s quality=speed async_depth=%s forced_idr=%d",
                     name.constData(), usage, asyncDepth ? "1" : "driver", m->forcedKeys);
             } else if (name == "libvpx-vp9" || name == "libaom-av1") {
@@ -295,7 +296,7 @@ bool LiveVideoEncoder::open(const LiveVideoConfig& config, Backend backend) {
                             if (frame.pts != pts) continue;
                             if (!frame.key) {
                                 m->error = "Encoder did not honor the requested key frame";
-                                DEBUG_WARN(DEBUG_CATEGORY_VIDEO,
+                                CODEC_LOG(DEBUG_LEVEL_WARN, DEBUG_CATEGORY_VIDEO,
                                     "desktop encoder probe returned non-key name=%s pts=%llu attempt=%d received=%d",
                                     name.constData(), (unsigned long long)pts, attempt, received);
                                 return false;
@@ -303,7 +304,7 @@ bool LiveVideoEncoder::open(const LiveVideoConfig& config, Backend backend) {
                             verified = {frame};
                             if (constrained && !verifiedProfile(config, verified)) {
                                 m->error = "Encoder output violates the call bitstream contract";
-                                DEBUG_WARN(DEBUG_CATEGORY_VIDEO, "call GPU probe rejected KEY name=%s pts=%llu attempt=%d",
+                                CODEC_LOG(DEBUG_LEVEL_WARN, DEBUG_CATEGORY_VIDEO, "call GPU probe rejected KEY name=%s pts=%llu attempt=%d",
                                     name.constData(), (unsigned long long)pts, attempt);
                                 return false;
                             }
@@ -315,26 +316,26 @@ bool LiveVideoEncoder::open(const LiveVideoConfig& config, Backend backend) {
                         output.clear();
                     }
                     m->error = "Encoder did not produce a key frame within the startup probe limit";
-                    DEBUG_WARN(DEBUG_CATEGORY_VIDEO,
+                    CODEC_LOG(DEBUG_LEVEL_WARN, DEBUG_CATEGORY_VIDEO,
                         "desktop encoder probe key delayed beyond limit name=%s pts=%llu max_delay_frames=%d received=%d",
                         name.constData(), (unsigned long long)pts, maxDelayFrames, received);
                     return false;
                 };
                 QList<LiveEncodedFrame> output;
                 if (!probeKey(0, output)) {
-                    DEBUG_WARN(DEBUG_CATEGORY_VIDEO, "desktop encoder initial KEY probe failed name=%s error=%s",
+                    CODEC_LOG(DEBUG_LEVEL_WARN, DEBUG_CATEGORY_VIDEO, "desktop encoder initial KEY probe failed name=%s error=%s",
                         name.constData(), qPrintable(m->error));
                     break;
                 }
                 if (!m->forcedKeys) {
-                    DEBUG_INFO(DEBUG_CATEGORY_VIDEO,
+                    CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_VIDEO,
                         "desktop AMF uses periodic IDR name=%s gop_frames=%d forced_key_requests=disabled",
                         name.constData(), c->gop_size);
                 } else {
                     output.clear();
                     const uint64_t forcedKeyPts = (1000000 / config.fps) * (maxDelayFrames + 2);
                     if (!probeKey(forcedKeyPts, output)) {
-                        DEBUG_WARN(DEBUG_CATEGORY_VIDEO, "desktop encoder forced KEY probe failed name=%s error=%s",
+                        CODEC_LOG(DEBUG_LEVEL_WARN, DEBUG_CATEGORY_VIDEO, "desktop encoder forced KEY probe failed name=%s error=%s",
                             name.constData(), qPrintable(m->error));
                         break;
                     }
@@ -350,13 +351,13 @@ bool LiveVideoEncoder::open(const LiveVideoConfig& config, Backend backend) {
                     if (!settings.isEmpty()) settings += ' ';
                     settings += QByteArray(option) + '=' + (result >= 0 ? QByteArray::number(value) : QByteArray("unavailable"));
                 }
-                DEBUG_INFO(DEBUG_CATEGORY_DEBUG,
+                CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_DEBUG,
                     "AMF effective settings encoder=%s %s target_bps=%lld max_bps=%lld vbv_bits=%d qmin=%d qmax=%d "
                     "time_base=%d/%d framerate=%d/%d; driver trace requires debug=trace",
                     name.constData(), settings.constData(), (long long)c->bit_rate, (long long)c->rc_max_rate, c->rc_buffer_size,
                     c->qmin, c->qmax, c->time_base.num, c->time_base.den, c->framerate.num, c->framerate.den);
             }
-            DEBUG_INFO(DEBUG_CATEGORY_VIDEO,
+            CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_VIDEO,
                 "desktop encoder ready name=%s codec=%d size=%dx%d fps=%d bitrate=%d level=%d refs=%d vbv=%d profile_verified=%d "
                 "forced_keys=%d max_qp=%d dynamic_qp=%d threads=%d thread_type=%d",
                 name.constData(), config.codec, config.width, config.height, config.fps, config.bitrate,
@@ -369,14 +370,14 @@ bool LiveVideoEncoder::open(const LiveVideoConfig& config, Backend backend) {
 #else
     m->error = "FFmpeg is unavailable";
 #endif
-    DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "desktop encoder open failed codec=%d backend=%d: %s",
+    CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO, "desktop encoder open failed codec=%d backend=%d: %s",
         config.codec, int(backend), qPrintable(m->error)); return false;
 }
 
 bool LiveVideoEncoder::encode(const QImage& image, uint64_t pts, bool key, QList<LiveEncodedFrame>& output, bool finish) {
 #ifdef HAVE_FFMPEG
     if (!m->codec || !m->frame || pts > INT64_MAX || (finish && !image.isNull())) {
-        m->error = "Invalid video frame"; DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "desktop encode invalid frame/state"); return false;
+        m->error = "Invalid video frame"; CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO, "desktop encode invalid frame/state"); return false;
     }
     QElapsedTimer timer; timer.start();
     if (!m->reportTimer.isValid()) m->reportTimer.start();
@@ -418,7 +419,7 @@ bool LiveVideoEncoder::encode(const QImage& image, uint64_t pts, bool key, QList
         }
         if (constrained && m->timestamps.size() >= 8) {
             m->error = "GPU encoder exceeded the bounded input pipeline";
-            DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "call encoder stalled name=%s pending=%zu pts=%llu",
+            CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO, "call encoder stalled name=%s pending=%zu pts=%llu",
                 qPrintable(m->name), m->timestamps.size(), (unsigned long long)pts); return false;
         }
         bool forceKey = key && (m->forcedKeys || m->submittedFrames == 0);
@@ -464,7 +465,7 @@ bool LiveVideoEncoder::encode(const QImage& image, uint64_t pts, bool key, QList
                     m->headers->time_base_in = m->codec->time_base;
                     diagnostic = av_bsf_init(m->headers);
                 }
-                if (diagnostic >= 0) DEBUG_INFO(DEBUG_CATEGORY_DEBUG,
+                if (diagnostic >= 0) CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_DEBUG,
                     "HEVC KEY header diagnostics enabled name=%s; slice_QP=26+init_qp_minus26+slice_qp_delta",
                     qPrintable(m->name));
             }
@@ -475,7 +476,7 @@ bool LiveVideoEncoder::encode(const QImage& image, uint64_t pts, bool key, QList
                 av_packet_free(&copy);
             }
             if (diagnostic < 0) {
-                DEBUG_WARN(DEBUG_CATEGORY_VIDEO, "HEVC header diagnostics disabled name=%s pts=%lld error=%s",
+                CODEC_LOG(DEBUG_LEVEL_WARN, DEBUG_CATEGORY_VIDEO, "HEVC header diagnostics disabled name=%s pts=%lld error=%s",
                     qPrintable(m->name), (long long)packet->pts, qPrintable(ffError(diagnostic)));
                 av_bsf_free(&m->headers);
             }
@@ -484,7 +485,7 @@ bool LiveVideoEncoder::encode(const QImage& image, uint64_t pts, bool key, QList
         encoded.pts = packet->pts >= 0 ? static_cast<uint64_t>(packet->pts) : pts;
         if (constrained) {
             if (m->timestamps.empty() || packet->pts != m->timestamps.front().first) {
-                DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "call GPU output PTS mismatch name=%s packet=%lld expected=%lld pending=%zu",
+                CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO, "call GPU output PTS mismatch name=%s packet=%lld expected=%lld pending=%zu",
                     qPrintable(m->name), (long long)packet->pts,
                     (long long)(m->timestamps.empty() ? -1 : m->timestamps.front().first), m->timestamps.size());
                 result = AVERROR_INVALIDDATA; break;
@@ -519,7 +520,7 @@ bool LiveVideoEncoder::encode(const QImage& image, uint64_t pts, bool key, QList
         auto& frameMax = producedKey ? m->keyMax : m->deltaMax;
         frameMax = std::max(frameMax, totalUs);
         if (totalUs > 100000 && !m->slowReported) {
-            DEBUG_WARN(DEBUG_CATEGORY_DEBUG,
+            CODEC_LOG(DEBUG_LEVEL_WARN, DEBUG_CATEGORY_DEBUG,
                 "video encoder slow frame name=%s size=%dx%d pts=%llu key=%d requested_key=%d "
                 "total_us=%lld prepare_us=%lld submit_us=%lld drain_us=%lld",
                 qPrintable(m->name), m->config.width, m->config.height, (unsigned long long)pts, producedKey, key,
@@ -542,12 +543,12 @@ bool LiveVideoEncoder::encode(const QImage& image, uint64_t pts, bool key, QList
             qPrintable(m->name), (unsigned long long)pts);
         if (finish && !m->timestamps.empty()) {
             m->error = "Encoder did not drain all accepted inputs";
-            DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "call encoder drain incomplete name=%s pending=%zu",
+            CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO, "call encoder drain incomplete name=%s pending=%zu",
                 qPrintable(m->name), m->timestamps.size()); return false;
         }
         return true;
     }
-    if (result < 0) { m->error = ffError(result); DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "desktop encode failed name=%s PTS=%llu: %s",
+    if (result < 0) { m->error = ffError(result); CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO, "desktop encode failed name=%s PTS=%llu: %s",
         qPrintable(m->name), (unsigned long long)pts, qPrintable(m->error)); return false; }
     return true;
 #else
@@ -571,13 +572,14 @@ QList<int> LiveVideoEncoder::available(Backend backend) {
 }
 
 bool LiveVideoEncoder::setBitrate(int bitrate) {
-    if (bitrate < 64000 || bitrate > 16000000) { DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "desktop live bitrate invalid value=%d", bitrate); return false; }
+    if (bitrate < 64000 || bitrate > 16000000) { CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO,
+        "desktop live bitrate invalid value=%d", bitrate); return false; }
 #ifdef HAVE_FFMPEG
     // libx264 перечитывает эти три значения через reconfig_encoder при подаче следующего кадра.
     if (m->codec && m->name == "libx264" && m->config.profile == LiveVideoProfile::Automatic) {
         m->codec->bit_rate = m->codec->rc_max_rate = bitrate;
         m->codec->rc_buffer_size = m->config.vbvBits ? m->config.vbvBits : bitrate / 4; m->config.bitrate = bitrate;
-        DEBUG_INFO(DEBUG_CATEGORY_VIDEO, "desktop encoder bitrate updated in place name=libx264 bitrate=%d", bitrate); return true;
+        CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_VIDEO, "desktop encoder bitrate updated in place name=libx264 bitrate=%d", bitrate); return true;
     }
 #endif
     DEBUG_DEBUG(DEBUG_CATEGORY_VIDEO, "desktop bitrate needs encoder replacement name=%s", qPrintable(m->name)); return false;
@@ -596,13 +598,14 @@ bool LiveVideoEncoder::canSetMaxQp() const {
 bool LiveVideoEncoder::setMaxQp(int qp) {
     if (qp < 0 || qp > 51 || !canSetMaxQp()) {
         m->error = "Live QP adjustment is unavailable";
-        DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "desktop live QP ceiling unavailable name=%s qp=%d", qPrintable(m->name), qp); return false;
+        CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO,
+            "desktop live QP ceiling unavailable name=%s qp=%d", qPrintable(m->name), qp); return false;
     }
 #ifdef HAVE_FFMPEG
     int result = m->name.endsWith("_amf") ? av_opt_set_int(m->codec->priv_data, "utun_qp_max", qp, 0) : 0;
     if (result < 0) {
         m->error = ffError(result);
-        DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "desktop live QP ceiling failed name=%s qp=%d error=%s",
+        CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_VIDEO, "desktop live QP ceiling failed name=%s qp=%d error=%s",
             qPrintable(m->name), qp, qPrintable(m->error)); return false;
     }
     m->codec->qmin = 0; m->codec->qmax = qp;
diff --git a/tools/chatgui/src/main.cpp b/tools/chatgui/src/main.cpp
index f5859843..da40c6bf 100644
--- a/tools/chatgui/src/main.cpp
+++ b/tools/chatgui/src/main.cpp
@@ -21,6 +21,8 @@
 #include "call_camera_capture.h"
 #include "call_video_engine.h"
 #include "single_instance.h"
+#include "desktop_integration.h"
+#include "gui_log.h"
 #include "config_parser.h"
 #include <cstdio>
 #include <cstring>
@@ -112,10 +114,13 @@ int main(int argc, char *argv[]) {
     debug_config_init();
     /* До чтения конфига видны запуск и IPC; затем уровень заменяет настройка профиля. */
     debug_set_level(DEBUG_LEVEL_INFO);
+    installGuiLogHandler();
 #ifdef _WIN32
     const bool consoleAttached = attach_parent_console();
 #endif
 #ifdef Q_OS_LINUX
+    /* libva пишет INFO напрямую в stderr; ошибки сохраняем, явную настройку пользователя не заменяем. */
+    if (!qEnvironmentVariableIsSet("LIBVA_MESSAGING_LEVEL")) qputenv("LIBVA_MESSAGING_LEVEL", "1");
     /* На Wayland композитор владеет позицией окна (move() игнорируется) —
      * для полноценного ручного move/resize с пропорцией запускаемся через XWayland. */
     if (!qEnvironmentVariableIsSet("QT_QPA_PLATFORM"))
@@ -125,6 +130,7 @@ int main(int argc, char *argv[]) {
     app.setApplicationName("vibechat");
     app.setApplicationVersion(QStringLiteral(VIBECHAT_VERSION));
     app.setDesktopFileName("org.utun.vibechat");
+    registerDesktopApplication(QCoreApplication::applicationFilePath());
     app.setWindowIcon(QIcon(":/icons/app_icon.png"));
     app.setQuitOnLastWindowClosed(false);
     const bool minimized = app.arguments().contains(QStringLiteral("--minimized"));
@@ -332,6 +338,7 @@ int main(int argc, char *argv[]) {
     QString lvl = cfg.debugLevel().trimmed();
     if (lvl.isEmpty()) lvl = QStringLiteral("info");
     debug_apply_global_level(lvl.toUtf8().constData());
+    if (!cfg.debugCategories().trimmed().isEmpty()) debug_parse_config(cfg.debugCategories().toUtf8().constData());
     DEBUG_INFO(DEBUG_CATEGORY_GENERAL, "vibechat: version=%s", qPrintable(app.applicationVersion()));
     DEBUG_INFO(DEBUG_CATEGORY_GENERAL, "GUI dark palette: window=%s base=%s alternate=%s button=%s light=%s",
                qPrintable(p.color(QPalette::Window).name()), qPrintable(p.color(QPalette::Base).name()),
diff --git a/tools/chatgui/src/mainwindow.cpp b/tools/chatgui/src/mainwindow.cpp
index 2b1b8a8d..12a81bad 100644
--- a/tools/chatgui/src/mainwindow.cpp
+++ b/tools/chatgui/src/mainwindow.cpp
@@ -509,7 +509,7 @@ void MainWindow::setupBridgeCallbacks() {
     gui_bridge_set_member_updated_cb(onMemberUpdatedCallback);
     gui_bridge_set_member_removed_cb(onMemberRemovedCallback);
     gui_bridge_set_my_node_id_cb([](uint64_t nid) {
-        qDebug("MainWindow: MY_NODE_ID setMyNodeId(%016llx)", (unsigned long long)nid);
+        DEBUG_DEBUG(DEBUG_CATEGORY_CHAT, "MainWindow: MY_NODE_ID setMyNodeId(%016llx)", (unsigned long long)nid);
         if (s_mainWindow && s_mainWindow->m_db) s_mainWindow->m_db->setMyNodeId((quint64)nid);
         if (AvatarManager::instance()) AvatarManager::instance()->initialize();
     });
diff --git a/tools/chatgui/src/video_codec_log.h b/tools/chatgui/src/video_codec_log.h
new file mode 100644
index 00000000..e1b04f7c
--- /dev/null
+++ b/tools/chatgui/src/video_codec_log.h
@@ -0,0 +1,19 @@
+// Диагностика codec: scoped-проба понижает ожидаемые отказы до debug только в своём потоке.
+// Создать VideoCodecProbe на время проверки; CODEC_LOG сохраняет обычный уровень вне неё.
+#pragma once
+#include "../../../src/video/video.h"
+#include "debug_config.h"
+
+class VideoCodecProbe {
+public:
+    VideoCodecProbe() { video_codec_probe_begin(); }
+    ~VideoCodecProbe() { video_codec_probe_end(); }
+    VideoCodecProbe(const VideoCodecProbe&) = delete;
+    VideoCodecProbe& operator=(const VideoCodecProbe&) = delete;
+};
+
+#define CODEC_LOG(level, category, ...) do { \
+    const auto codecLevel = static_cast<debug_level_t>(video_codec_log_level(level)); \
+    if (debug_should_output(codecLevel, category)) \
+        debug_output(codecLevel, category, __FUNCTION__, __FILE__, __LINE__, __VA_ARGS__); \
+} while (0)
diff --git a/tools/chatgui/tests/test_desktop_integration.cpp b/tools/chatgui/tests/test_desktop_integration.cpp
new file mode 100644
index 00000000..9fbc62bd
--- /dev/null
+++ b/tools/chatgui/tests/test_desktop_integration.cpp
@@ -0,0 +1,44 @@
+// Настоящий desktop parser/launcher: путь с пробелами, кавычками и спецсимволами сохраняется без shell-подстановок.
+#include <QtTest>
+#include <QDir>
+#include <QFile>
+#include <QProcess>
+#include <QStandardPaths>
+#include <QTemporaryDir>
+#include "../src/desktop_integration.h"
+#include "debug_config.h"
+
+class DesktopTest : public QObject {
+    Q_OBJECT
+private slots:
+    void registrationAndLaunch() {
+        QTemporaryDir directory; QVERIFY(directory.isValid());
+        qputenv("XDG_DATA_HOME", directory.path().toUtf8());
+        qputenv("XDG_DATA_DIRS", directory.filePath("system-data").toUtf8());
+        const QString executable = directory.filePath("space quote\" dollar$ backtick` percent% slash\\-тест");
+        QFile script(executable); QVERIFY(script.open(QIODevice::WriteOnly));
+        script.write("#!/bin/sh\nprintf '%s' \"$0\" > \"$DESKTOP_RESULT\"\n"); script.close();
+        QVERIFY(script.setPermissions(QFile::ReadOwner | QFile::WriteOwner | QFile::ExeOwner));
+        QVERIFY(registerDesktopApplication(executable));
+        const QString path = directory.filePath("applications/org.utun.vibechat.desktop");
+        QFile file(path); QVERIFY(file.open(QIODevice::ReadOnly)); const auto original = file.readAll(); file.close();
+        QVERIFY(registerDesktopApplication("/must/not/replace/existing/entry"));
+        QVERIFY(file.open(QIODevice::ReadOnly)); QCOMPARE(file.readAll(), original); file.close();
+        const auto gio = QStandardPaths::findExecutable("gio");
+        if (gio.isEmpty()) QSKIP("gio unavailable: desktop entry created; launcher validation needs GLib tools");
+        const QString output = directory.filePath("result"); qputenv("DESKTOP_RESULT", output.toUtf8());
+        QProcess process; process.start(gio, {"launch", path}); QVERIFY(process.waitForFinished(5000));
+        QCOMPARE(process.exitStatus(), QProcess::NormalExit);
+        QVERIFY2(process.exitCode() == 0, (process.readAllStandardError() + "\nentry:\n" + original).constData());
+        QFile result(output); QTRY_VERIFY(result.exists()); QVERIFY(result.open(QIODevice::ReadOnly));
+        QCOMPARE(QString::fromUtf8(result.readAll()), executable);
+    }
+    void registrationFailure() {
+        QTemporaryDir directory; QVERIFY(directory.isValid());
+        qputenv("XDG_DATA_HOME", directory.path().toUtf8());
+        QFile obstacle(directory.filePath("applications")); QVERIFY(obstacle.open(QIODevice::WriteOnly)); obstacle.close();
+        QVERIFY(!registerDesktopApplication("/example/vibechat"));
+    }
+};
+QTEST_GUILESS_MAIN(DesktopTest)
+#include "test_desktop_integration.moc"
diff --git a/tools/chatgui/tests/test_video_diagnostics.cpp b/tools/chatgui/tests/test_video_diagnostics.cpp
new file mode 100644
index 00000000..87220ae7
--- /dev/null
+++ b/tools/chatgui/tests/test_video_diagnostics.cpp
@@ -0,0 +1,87 @@
+// Пробы codec не скрывают рабочие ошибки в соседнем потоке и восстанавливают уровни после завершения.
+#include <QtTest>
+#include <QFile>
+#include <QLoggingCategory>
+#include <QTemporaryDir>
+#include <mutex>
+#include <thread>
+#include <vector>
+#include "../src/video_codec_log.h"
+#include "../src/gui_log.h"
+extern "C" {
+#include <libavutil/log.h>
+}
+
+namespace {
+struct Message { int level; QString text; };
+std::mutex lock;
+std::vector<Message> messages;
+void capture(int level, const char*, const char* text) {
+    std::lock_guard<std::mutex> guard(lock); messages.push_back({level, QString::fromUtf8(text)});
+}
+}
+
+class DiagnosticsTest : public QObject {
+    Q_OBJECT
+private slots:
+    void init() {
+        debug_config_init(); debug_set_level(DEBUG_LEVEL_DEBUG); debug_enable_console(0);
+        messages.clear(); debug_set_log_hook(capture); video_ffmpeg_init();
+    }
+    void cleanup() { debug_set_log_hook(nullptr); }
+    void probeLevelsRepeatsAndConcurrentErrors() {
+        {
+            VideoCodecProbe probe;
+            av_log(nullptr, AV_LOG_ERROR, "GPU unavailable\n");
+            av_log(nullptr, AV_LOG_ERROR, "GPU unavailable\n");
+            {
+                VideoCodecProbe nested;
+                av_log(nullptr, AV_LOG_ERROR, "GPU unavailable\n");
+                CODEC_LOG(DEBUG_LEVEL_ERROR, DEBUG_CATEGORY_CALL, "expected probe failure");
+            }
+            std::thread playback([] { av_log(nullptr, AV_LOG_ERROR, "live decoder failure\n"); }); playback.join();
+            QCOMPARE(video_codec_log_level(DEBUG_LEVEL_WARN), int(DEBUG_LEVEL_DEBUG));
+        }
+        av_log(nullptr, AV_LOG_ERROR, "runtime failure after probe\n");
+        QCOMPARE(messages.size(), size_t(5));
+        QCOMPARE(messages[0].level, int(DEBUG_LEVEL_DEBUG)); QVERIFY(messages[0].text.contains("GPU unavailable"));
+        QCOMPARE(messages[1].level, int(DEBUG_LEVEL_DEBUG)); QVERIFY(messages[1].text.contains("expected probe failure"));
+        QCOMPARE(messages[2].level, int(DEBUG_LEVEL_ERROR)); QVERIFY(messages[2].text.contains("live decoder failure"));
+        QCOMPARE(messages[3].level, int(DEBUG_LEVEL_DEBUG)); QVERIFY(messages[3].text.contains("repeated=2"));
+        QCOMPARE(messages[4].level, int(DEBUG_LEVEL_ERROR)); QVERIFY(messages[4].text.contains("runtime failure after probe"));
+    }
+    void infoLevelSkipsProbeDetails() {
+        debug_set_level(DEBUG_LEVEL_INFO);
+        {
+            VideoCodecProbe probe;
+            av_log(nullptr, AV_LOG_ERROR, "unsupported hardware mode\n");
+            av_log(nullptr, AV_LOG_ERROR, "unsupported hardware mode\n");
+            CODEC_LOG(DEBUG_LEVEL_INFO, DEBUG_CATEGORY_CALL, "per-mode probe details");
+        }
+        QVERIFY(messages.empty());
+        CODEC_LOG(DEBUG_LEVEL_WARN, DEBUG_CATEGORY_CALL, "actual playback warning");
+        QCOMPARE(messages.size(), size_t(1)); QCOMPARE(messages[0].level, int(DEBUG_LEVEL_WARN));
+    }
+    void restoresFfmpegCallback() {
+        av_log_set_callback(av_log_default_callback);
+        video_ffmpeg_init();
+        av_log(nullptr, AV_LOG_ERROR, "restored callback\n");
+        QCOMPARE(messages.size(), size_t(1)); QVERIFY(messages[0].text.contains("restored callback"));
+    }
+    void qtAndFfmpegUseCommonFile() {
+        QTemporaryDir directory; QVERIFY(directory.isValid());
+        const auto path = directory.filePath("chatgui.log"); debug_enable_file_output(path.toUtf8().constData(), 0);
+        const auto previous = installGuiLogHandler();
+        const QLoggingCategory category("qt.multimedia.test");
+        qWarning("portal diagnostic");
+        qCWarning(category, "codec diagnostic");
+        av_log(nullptr, AV_LOG_ERROR, "FFmpeg diagnostic\n");
+        qInstallMessageHandler(previous); debug_disable_file_output();
+        QFile file(path); QVERIFY(file.open(QIODevice::ReadOnly)); const auto text = file.readAll();
+        QVERIFY(text.contains("[WARN] [general]")); QVERIFY(text.contains("Qt[default]: portal diagnostic"));
+        QVERIFY(text.contains("[WARN] [video]")); QVERIFY(text.contains("Qt[qt.multimedia.test]: codec diagnostic"));
+        QVERIFY(text.contains("[ERROR] [video]")); QVERIFY(text.contains("ffmpeg: FFmpeg diagnostic"));
+    }
+};
+QTEST_GUILESS_MAIN(DiagnosticsTest)
+#include "test_video_diagnostics.moc"