Widget dragging is really unstable...

Someone please help…I want to make a drag and drop UI but it barely works properly.
To be precise, the drag itself works, but the mouse event to trigger it doesn’t work.

I have included an image set to Visible at the top, but it may not respond. “it may not respond” means, that it may react if certain conditions are met. For example, dragging works if i add a Print String to a process or have the Widget Reflector running.

I have no idea why…I’ve looked into it and I don’t understand why this happens…
Is this a bug?

Hey, I’m really in trouble.
Does anyone know how to fix it?

New findings.

Detect drag if pressed will stop working after every editor restart, and will work again after compiling the widget again.
But this is only in the editor and doesn’t work at all in the standalone mode.
However, when I checked with PrintString, it seemed like the execution for Detect drag if pressed was processed. So this is not a mouse event but rather a problem with Detect drag if pressed.

Does anyone know why it’s not working? I will provide you with all the information you need to solve the problem.

Still not resolved.
Has anyone encountered this issue? Not even a hint?