Play button stays highlighted after PIE has ended

Play button stays highlighted after PIE has ended until the user moves mouse over the Play button again.

Regression (Yes) issue (does not) occur in 4.10.4.

1. Open Editor (any project)
2. Press PIE
3. Move mouse away from PIE button
4. Presss ESC to exit PIE

Results
After PIE has ended, the Play button remains highlighted until the mouse has hovered over it again.

Expected
The PIE button immediately removes the highlight as it is no longer in use/hovered over.

Various small UI bugs in 4.12 prev