Installed Elements 2021 on my Win10 PC a month ago. All of a sudden yesterday a little "commit/cancel" box popped up at the bottom of the photo I was cropping--couldn't be closed or moved, and it prevented me from further adjusting the crop lines after I'd first released the mouse button. My old PS never did that, and Elements hadn't done it with the two photos I'd just cropped in the same session! Where did it come from? More important, how do I disable it?
The commit/cancel button always appears when you release the mouse button for your initial crop. Are you saying that you can't hit either the cancel or commit option? Does anything change if you hit the Esc key? What happens if you start the crop from a different corner? Please show us a screenshot of the problem.
That behavior of the commit/cancel icon is not new and there has been an number of questions about it in various Elements forums.
The solution is not intuitive, it implies understanding (admitting) that you are not writing directly on your canvas, you are writing on a transparent text 'layer' (in French it is called a 'calque'). So, you only have to concentrate on the letters themselves when writing higher on your canvas so that the commit button is visible, then you move the text 'layer' down to the right definitive position.