From 2244d70a94288091d4c9f9f8bac0aaa376d8d40e Mon Sep 17 00:00:00 2001
From: Jehan <jehan@girinstud.io>
Date: Thu, 12 Jun 2025 01:55:38 +0200
Subject: [PATCH] Issue #13183: use the renamed desktop filename in Flatpak.

Since MR !2158, we set the desktop name as prgname, because that's what
is expected for Wayland. But this doesn't work on Flatpak where the
desktop file is renamed (and even to different names for the stable/beta
vs. nightly flatpaks). This commit adds some special-casing when we
detect we are inside a flatpak environment.

Note that on X11 (whether or not we are in flatpak), we just always use
the original desktop name, because then it will be set as windows'
WM_CLASS which will also match the StartupWMClass key we set in the
desktop file (cf. previous commit).
---
 app/main.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)

diff --git a/app/main.c b/app/main.c
index 9db78ed8e3..9711c6c1b8 100644
--- a/app/main.c
+++ b/app/main.c
@@ -46,6 +46,9 @@
 
 #ifndef GIMP_CONSOLE_COMPILATION
 #include <gtk/gtk.h>
+#ifdef GDK_WINDOWING_X11
+#include <gdk/gdkx.h>
+#endif
 #else
 #include <gdk-pixbuf/gdk-pixbuf.h>
 #endif
@@ -548,6 +551,9 @@ main (int    argc,
   GFile          *user_gimprc_file   = NULL;
   GOptionGroup   *gimp_group         = NULL;
   gchar          *backtrace_file     = NULL;
+#ifndef GIMP_CONSOLE_COMPILATION
+  GKeyFile       *flatpak_keyfile;
+#endif
   gint            retval;
   gint            i;
 
@@ -755,6 +761,47 @@ main (int    argc,
       app_exit (EXIT_FAILURE);
     }
 
+#if GLIB_CHECK_VERSION(2,72,0)
+  /* g_set_prgname() can only be called several times since 2.72.0. */
+#ifndef GIMP_CONSOLE_COMPILATION
+  g_return_val_if_fail (gdk_display_get_default () != NULL, EXIT_FAILURE);
+
+  flatpak_keyfile = g_key_file_new ();
+
+  if (
+#ifdef GDK_WINDOWING_X11
+      ! GDK_IS_X11_DISPLAY (gdk_display_get_default ()) &&
+#endif
+      g_key_file_load_from_file (flatpak_keyfile, "/.flatpak-info", G_KEY_FILE_NONE, NULL))
+    {
+      /* Flatpak renames the desktop file. The .flatpak-info file tells
+       * us the right desktop name we must associate our process to,
+       * especially as we have flatpaks with different IDs.
+       *
+       * This logic should not apply on X11 which will instead
+       * apparently use the StartupWMClass set in the desktop file and
+       * expect it to be the same as the name set by g_set_prgname().
+       *
+       * Cf. #13183 and #14233.
+       */
+      gchar *flatpak_name = g_key_file_get_string (flatpak_keyfile, "Application", "name", NULL);
+
+      if (flatpak_name != NULL)
+        {
+          g_set_prgname (flatpak_name);
+          g_free (flatpak_name);
+        }
+      /* The else case should never happen unless we are in some kind of
+       * broken flatpak environment or somehow in a non-flatpak
+       * environment with a .flatpak-info file at the root, which seems
+       * improbable. Fail silently.
+       */
+    }
+
+  g_key_file_free (flatpak_keyfile);
+#endif
+#endif
+
   if (no_interface || be_verbose || console_messages || batch_commands != NULL)
     gimp_open_console_window ();