Postpone post_init() until opengl is initialized on all systems.

Revert on win

src/slic3r/GUI/GUI_App.cpp

@@ -887,13 +887,9 @@ wxGLContext* GUI_App::init_glcontext(wxGLCanvas& canvas)
 
 bool GUI_App::init_opengl()
 {
-#ifdef __linux__
     bool status = m_opengl_mgr.init_gl();
     m_opengl_initialized = true;
     return status;
-#else
-    return m_opengl_mgr.init_gl();
-#endif
 }
 
 // gets path to PrusaSlicer.ini, returns semver from first line comment
@@ -1370,12 +1366,15 @@ bool GUI_App::on_init_inner()
 
         // An ugly solution to GH #5537 in which GUI_App::init_opengl (normally called from events wxEVT_PAINT
         // and wxEVT_SET_FOCUS before GUI_App::post_init is called) wasn't called before GUI_App::post_init and OpenGL wasn't initialized.
-#ifdef __linux__
-        if (! m_post_initialized && m_opengl_initialized) {
+        // Since issue #9774 Where same problem occured on MacOS Ventura, we decided to have this check on MacOS as well.
+
+#ifdef __linux__ || __APPLE__
+        if (!m_post_initialized && m_opengl_initialized) {
 #else
-        if (! m_post_initialized) {
+        if (!m_post_initialized) {
 #endif
             m_post_initialized = true;
+
 #ifdef WIN32
             this->mainframe->register_win32_callbacks();
 #endif

src/slic3r/GUI/GUI_App.hpp

@@ -127,9 +127,7 @@ private:
     bool            m_last_app_conf_lower_version{ false };
     EAppMode        m_app_mode{ EAppMode::Editor };
     bool            m_is_recreating_gui{ false };
-#ifdef __linux__
     bool            m_opengl_initialized{ false };
-#endif
 
     wxColour        m_color_label_modified;
     wxColour        m_color_label_sys;