It seems the parent's active child can still get modified if all windows are not yet created
Window::ActivateEx checks for '!destroyed', but does not check for 'created'
(Adding && !created to that ActivateEx check was an alternative fix, but this fix seemed safer)
ResPtr ptr;
if(parent)
+ {
stopwatching(parent, font);
+ if(parent.activeChild == this)
+ parent.activeChild = null;
+ if(parent.activeClient == this)
+ parent.activeClient = null;
+ }
if(!destroyed)
{