Fix initial focus problem for hidden windows under Mac

Assume that hidden windows do accept focus because, even if this is
still wrong, in general, it is less harmful than wrongly returning false
from CanFocus() for them.

Closes #18987.

src/osx/cocoa/window.mm

@@ -3094,12 +3094,11 @@ bool wxWidgetCocoaImpl::CanFocus() const
 {
     if ( !IsVisible() )
     {
-        // It's useless to call canBecomeKeyView in this case, it will always
+        // canBecomeKeyView always returns false for hidden windows, but this
-        // return false. Try to return something reasonable ourselves, knowing
+        // could be wrong because the window could still accept focus once it
-        // that most controls are not focusable when full keyboard access if
+        // becomes visible, so we have no choice but to return true here to
-        // off and wxNSTextViewControl overrides CanFocus() to always return
+        // avoid situations in which the expected window doesn't get the focus.
-        // true anyhow.
+        return true;
-        return [NSApp isFullKeyboardAccessEnabled];
     }
 
     NSView* targetView = m_osxView;