White boxes instead of tooltip on element hover while debugging

While paused in the debugger, hovering over elements in the editor sometimes shows a white box instead of the expected tooltip content.

Moving the cursor away and back to the same element to hover a second time, shows the correct information.

Leaving the cursor on the element showing the white box for some time doesn't seem to change anything. It doesn't appear to be a slow load or something to that effect.

Maybe the large size of the file plays a role. In other projects, on smaller files, everything was normal. Actually, I was able to reproduce it on relatively small files too.