Bug with Slate and mouse events

I hope you can help me with this,

We found that by using some slate classes the mouse events do not get bubbled up correctly through the viewport even if the events are directly assigned as Unhandled. I’m attaching a project I built based on another community member’s code, hoping you can take a look at the bug.

How to check:

  1. Generate the project files through the .uproject and compile
  2. (Problem 1) When playing, try to hover your mouse over the box, you will see that the level blueprint’s “Cursor Over” events are not being called.
  3. (Problem 2) If you CLICK the box, the “Cursor Over” events are called
  4. (Cause) Go into SlateProblemPlayerController.cpp and comment out the line adding the slate widget to the viewport (line 15)

You can also check that the Widget in question has the events declared but is simply returning Unhandled, which should allow bubbling.
I believe this issue can also be replicated with UMG and the underlying cause is the same.

This is likely a bug in the engine’s event system but my knowledge does not go as far as allowing me to debug it fully and present a solution. Can you tell me how I can go around this problem without changing the engine code or if it will be fixed in the future?

Here is the project: Slate Problem

Best Regards,
Niktsuki

Is there anyone from the staff able to confirm this or explain what is wrong? :frowning:

Sorry for the trouble

I have the same issue