Hey Guys
this is really weird I have a huge window|square empty thing behind the editor, and is ONLY in the particular project, all other projects I open are OK
nothing seems to make it go away I don’t like it 
Did you undock the editor window by any ? That’s the background of the editor frame… can you try dragging the editor tab back into it?
Hi varomix,
That’s a known bug. What you’re seeing is the frame window. This usually happens when you drag the Level Editor tab out of it. We have plans to fix this, but it requires some more elaborate changes in how the Editor’s windows are managed, so I can’t give you an ETA yet.
In the meantime, if you are unable to drag the Level Editor window back into the frame, then you can delete the EditorUserSettings.ini file in your project’s /Saved/Config directory.
Resetting the UI Layout inside the editor used to help me fix this in Beta.
Oh it worked I just dragged the tab to it and is gone, man I don’t even know when I did that.
Thanks guys it was driving me crazy, not a bug, maybe just adding a note there like , Dock window or something like that.
It’s impossible to drag the editor tab back into the frame window. Dropping it in any spot just leaves in a separate window still.
drag from the TAB into the window behind
How did you reset the UI Layout? I’m having this problem too and redocking the tab isn’t working.
Dragging didn’t work for me (empty window didn’t accept the tab). Deleting the EditorUserSettings.ini did not have any effect. Had to reset the whole layout.
You are right, dragging the tab no longer works, can’t dock the window back into the container, I did Window Menu > Restore Layout and that Works
Hey guys,
I wanted to follow up on this. We are aware that the issue has regressed and are working on getting the tab to dock with slate properly once undocked. When there is a fix, we will include that information in an update announcement
Great to hear that, thanks for the update
if you delete your saved ini in the saved folder it will reset