fix: MASSIVELY improve mod restart/uninstall stability

Author: narknon

UE4SS/src/Mod/LuaMod.cpp

@@ -4261,6 +4261,25 @@ No overload found for function 'FPackageName:IsValidLongPackageName'.
         });
 
 
+        // Mark all hooks for this mod as scheduled_for_removal BEFORE closing Lua state
+        // This prevents hooks from firing with an invalid Lua state during the window between
+        // lua_close and the actual hook unregistration
+        for (auto& item : g_hooked_script_function_data)
+        {
+            if (item->mod == this)
+            {
+                item->scheduled_for_removal = true;
+            }
+        }
+
+        // Remove any pending game thread actions for this mod BEFORE closing Lua state
+        // Otherwise process_event_hook may try to execute actions with an invalid Lua state
+        // Note: action.lua points to m_hook_lua (a thread), so compare against that
+        // Must be done BEFORE m_hook_lua is set to nullptr
+        std::erase_if(m_game_thread_actions, [&](const SimpleLuaAction& action) {
+            return action.lua == m_hook_lua;
+        });
+
         if (m_hook_lua != nullptr)
         {
             m_hook_lua = nullptr; // lua_newthread results are handled by lua GC
@@ -4276,17 +4295,6 @@ No overload found for function 'FPackageName:IsValidLongPackageName'.
             lua_resetthread(m_main_lua->get_lua_state());
         }
 
-        // Mark all hooks for this mod as scheduled_for_removal BEFORE closing Lua state
-        // This prevents hooks from firing with an invalid Lua state during the window between
-        // lua_close and the actual hook unregistration
-        for (auto& item : g_hooked_script_function_data)
-        {
-            if (item->mod == this)
-            {
-                item->scheduled_for_removal = true;
-            }
-        }
-
         lua_close(lua().get_lua_state());
 
         // Unhook all UFunctions for this mod & remove from the map that keeps track of which UFunctions have been hooked

UE4SS/src/UE4SSProgram.cpp

@@ -1535,6 +1535,10 @@ namespace RC
 
         for (auto& mod : cpp_mods)
         {
+            if (!mod->is_installable())
+            {
+                continue;
+            }
             mod->uninstall();
         }