[Lazarus] Is this a bug? or what is problem can be?

[FreeMan]

[HINT] TWinControl.CreateWnd creating Handle during loading 
PGC_H:TTabControl csDesigning=False
QCoreApplication::postEvent: Unexpected null receiver
...
reopen form I get this error
[HINT] TWinControl.CreateWnd creating Handle during loading 
PGC_H:TTabControl csDesigning=False
TApplication.HandleException Access violation
   Stack trace:
   $00007F67CF31211D
...

After form destroy I get this errors. Form is not autocreate, when I 
need then create and onformclose use cafree, ondestroy event myform := nil;