From a blank project:
Create a blank widget with a CanvasPanel containing two buttons
Set the left button to IsFocuable = False
Create PlayerController to allow mouse controls (ShowMouseCursor = true and Enable Click Events = True)
Create a game mode to use the player controller.
Set begin play of the game mode to (add widget created in step 1. to viewport) and (SetInputModeUIOnly)
(Optional) You may have to restart the project at this point if your input doesn’t work (idk how to remove the “ShowMouseCursor with F1” in the top left without restarting)
Should end up with the bug shown in the gif below:
You can see this much easier by changing the image of the pressed state
I have run a few tests with the information provided, however I have been unable to reproduce this issue on our end. I noticed that you provided steps to reproduce this issue in a clean project. Does this mean you were able to reproduce this issue in a clean project or was the example done on a clean map? Could you provide a zipped down copy of the project used so that I could take a closer look?
This was from an empty map. I also forgot to mention this only happens on the first click so it might be hard to catch.
After taking a look at your project, I noticed that you do not have “Set input mode UIonly” setup correctly. I have provided an example below. I hope that this information helps.
What you have:
Correct setup example:
Make it a great day