Writer--large white block appeared, covering text. How to remove?

Don’t know how it happened, but it’s as if a new page appeared on top of an earlier one. There are no “block handles” that I can find. It won’t delete.

It just appeared in this document upon opening. I looked at the form toolbar, but can’t see anything applicable.

What is it, so I will not accidentally do this again, and how do I go about getting rid of it without damaging the text underneath?

Help will be greatly appreciated, since I don’t understand most of the more intricate help articles–or the fancy options they refer to.

Press F5 (Navigator) and see if there are a text box, an image, or so not expected.

Add Answer is reserved for solutions.

Press edit below your question if you want to add more information.

I pressed F5, went to Text Box, found 2 and deleted them both. That removed the large white block that was obscuring the text underneath.

Knowing about F5 is likely to be very useful in the future.