Add warnings about some build options and environment variables

Telegram/CMakeLists.txt

@@ -157,7 +157,7 @@ if (LINUX)
     endif()
 endif()
 
-if (LINUX AND (NOT TDESKTOP_DISABLE_GTK_INTEGRATION OR NOT DESKTOP_APP_DISABLE_DBUS_INTEGRATION))
+if (LINUX)
     find_package(PkgConfig REQUIRED)
     pkg_check_modules(GLIB2 REQUIRED IMPORTED_TARGET glib-2.0)
     pkg_check_modules(GOBJECT REQUIRED IMPORTED_TARGET gobject-2.0)
@@ -170,6 +170,7 @@ if (LINUX AND (NOT TDESKTOP_DISABLE_GTK_INTEGRATION OR NOT DESKTOP_APP_DISABLE_D
         PkgConfig::GIO
     )
 
+    target_compile_definitions(Telegram PRIVATE G_LOG_DOMAIN="Telegram")
     target_compile_options(Telegram PRIVATE -Wno-register)
 endif()
 

Telegram/SourceFiles/platform/linux/main_window_linux.cpp

@@ -44,6 +44,8 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include <QtDBus/QDBusMetaType>
 #endif // !DESKTOP_APP_DISABLE_DBUS_INTEGRATION
 
+#include <glib.h>
+
 namespace Platform {
 namespace {
 
@@ -737,6 +739,13 @@ void MainWindow::LibsLoaded() {
 	qDBusRegisterMetaType<IconPixmap>();
 	qDBusRegisterMetaType<IconPixmapList>();
 #endif // !DESKTOP_APP_DISABLE_DBUS_INTEGRATION
+
+	if (!qEnvironmentVariableIsSet(kDisableTrayCounter.utf8())) {
+		g_warning(
+			"You can disable tray icon counter with %s "
+			"and make it look better if it is monochrome.",
+			kDisableTrayCounter.utf8().constData());
+	}
 }
 
 void MainWindow::initTrayMenuHook() {

Telegram/SourceFiles/platform/linux/specific_linux.cpp

@@ -46,6 +46,8 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include <wayland-client.h>
 #endif // Qt < 5.13 && !DESKTOP_APP_QT_PATCHED
 
+#include <glib.h>
+
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <cstdlib>
@@ -62,6 +64,9 @@ using QtWaylandClient::QWaylandWindow;
 namespace Platform {
 namespace {
 
+constexpr auto kDisableGtkIntegration = "TDESKTOP_DISABLE_GTK_INTEGRATION"_cs;
+constexpr auto kIgnoreGtkIncompatibility = "TDESKTOP_I_KNOW_ABOUT_GTK_INCOMPATIBILITY"_cs;
+
 constexpr auto kDesktopFile = ":/misc/telegramdesktop.desktop"_cs;
 constexpr auto kSnapLauncherDir = "/var/lib/snapd/desktop/applications/"_cs;
 constexpr auto kIconName = "telegram"_cs;
@@ -644,7 +649,7 @@ bool IsStaticBinary() {
 bool UseGtkIntegration() {
 #ifndef TDESKTOP_DISABLE_GTK_INTEGRATION
 	static const auto Result = !qEnvironmentVariableIsSet(
-		"TDESKTOP_DISABLE_GTK_INTEGRATION");
+		kDisableGtkIntegration.utf8());
 
 	return Result;
 #endif // !TDESKTOP_DISABLE_GTK_INTEGRATION
@@ -1162,11 +1167,49 @@ void start() {
 	if (UseGtkIntegration()
 		&& !IsStaticBinary()
 		&& !qEnvironmentVariableIsSet(
-			"TDESKTOP_I_KNOW_ABOUT_GTK_INCOMPATIBILITY")) {
+			kIgnoreGtkIncompatibility.utf8())) {
+		g_warning(
+			"Unfortunately, GTK integration "
+			"conflicts with qgtk2 platformtheme and style. "
+			"Therefore, QT_QPA_PLATFORMTHEME "
+			"and QT_STYLE_OVERRIDE will be unset.");
+
+		g_warning(
+			"This can be ignored by setting %s environment variable "
+			"to any value, however, if qgtk2 theme or style is used, "
+			"this will lead to a crash.",
+			kIgnoreGtkIncompatibility.utf8().constData());
+
+		g_warning(
+			"GTK integration can be disabled by setting %s to any value. "
+			"Keep in mind that this will lead to clipboard issues "
+			"and tdesktop will be unable to get settings from GTK "
+			"(such as decoration layout, dark mode & more).",
+			kDisableGtkIntegration.utf8().constData());
+
 		qunsetenv("QT_QPA_PLATFORMTHEME");
 		qunsetenv("QT_STYLE_OVERRIDE");
 	}
 
+	if (!UseGtkIntegration()) {
+		g_warning(
+			"GTK integration was disabled on build or in runtime. "
+			"This will lead to clipboard issues and a lack of some features "
+			"(like Auto-Night Mode or system window controls layout).");
+	}
+
+#ifdef DESKTOP_APP_USE_PACKAGED_RLOTTIE
+	g_warning(
+		"Application has been built with foreign rlottie, "
+		"animated emojis won't be colored to the selected pack.");
+#endif // DESKTOP_APP_USE_PACKAGED_RLOTTIE
+
+#ifdef DESKTOP_APP_USE_PACKAGED_FONTS
+	g_warning(
+		"Application was built without embedded fonts, "
+		"this may lead to font issues.");
+#endif // DESKTOP_APP_USE_PACKAGED_FONTS
+
 	if(IsStaticBinary()
 		|| InAppImage()
 		|| InFlatpak()