Summary
When using CommonUI with Common Game Viewport and Activatable Widgets, disabling Project Settings → Common Input → Windows → Supports Mouse and Keyboard causes the Unreal Editor to enter a broken mouse/cursor state after starting and stopping PIE.
The issue affects the Editor itself, not only the game.
What Type of Bug are you experiencing?
Editor
Steps to Reproduce
Create or open a UE 5.6.1 project using CommonUI.
Enable the Common Game Viewport and use Activatable Widgets.
Go to Project Settings → Common Input → Windows.
Disable “Supports Mouse and Keyboard”.
Start PIE.
Stop PIE.
I tried to reproduce this on a blank project but couldn’t. So there seems to be some other variable affecting it.
Expected Result
Only the game’s input configuration should be affected. The Unreal Editor should continue to behave normally.
Observed Result
The Unreal Editor enters a broken mouse state. Examples include:
Resize cursors (double arrows) no longer appear on window borders or panel dividers.
The mouse cursor may disappear in Blueprint graphs.
General mouse interaction within the Editor becomes unreliable.
Re-enabling Supports Mouse and Keyboard and starting PIE again immediately restores normal Editor behavior.
Affects Versions
5.6
Platform(s)
Windows
Upload an image
the last .gif shows the drag and drop with and without mouse cursor. without being the broken state.