Create PluginManager instance as function-local static

Global statics gets destroyed last during the exit sequence, at that time static local wxConvFileName is already destroyed.

PluginManager flushes config file to disk during destruction, which result in accessing deleted object.
By making PluginManager function-local static we ensure that it will be deleted prior to wxConvFileName

libraries/lib-module-manager/PluginManager.cpp

@@ -321,9 +321,6 @@ bool PluginManager::RemoveConfig(ConfigurationType type, const PluginID & ID,
 //
 // ============================================================================
 
-// The one and only PluginManager
-std::unique_ptr<PluginManager> PluginManager::mInstance{};
-
 // ----------------------------------------------------------------------------
 // Creation/Destruction
 // ----------------------------------------------------------------------------
@@ -379,12 +376,8 @@ static PluginManager::ConfigFactory sFactory;
 
 PluginManager & PluginManager::Get()
 {
-   if (!mInstance)
-   {
-      mInstance.reset(safenew PluginManager);
-   }
-
-   return *mInstance;
+   static PluginManager instance;
+   return instance;
 }
 
 void PluginManager::Initialize(ConfigFactory factory)

libraries/lib-module-manager/PluginManager.h

@@ -231,8 +231,6 @@ class MODULE_MANAGER_API PluginManager final
    wxString ConvertID(const PluginID & ID);
 
 private:
-   friend std::default_delete<PluginManager>;
-   static std::unique_ptr<PluginManager> mInstance;
 
    bool IsDirty();
    void SetDirty(bool dirty = true);