Just checked it and it is just a text.
Ok, so it looks like this problem happens only when you drag over the progress bar.
I found another similar question and they said to make an invisible object on top of it.
It does not work for me though.
I also tried the onclick event of the progress bar, to set the cursor of the mouse to normal.
Unfortunately, it works only for click, not drag.
Also, just tried the 'every tick' 'set cursor to normal' and it does not work too.
(even though the cursor seems to continue to show as selecting text)
Update: I just opened a new project with a progress bar in it without events and seems like to be an issue.
So now I know 100% is the progress bar.