Take off an replaster.
Do you have a photo?
Best to remove them and patch.
Hi Marcia, I would use a contact paper. It comes in all kinds of colors, types and designs. and should stick to the glass. You can also paint the mirror tiles, but you will need to roughen the glass with steel wool and use a paint designed for glass.
Buy some Tile Covers and use them. They just peel and stick on. Best wishes. Otherwise Maybe hang a shower curtain across them or
hang a Picture...........
Are you able to remove the mirrors? You could also etch them with acid if you don't like the mirror finish
You could paint them
Marcia: if there are not a lot of them-- you could find artwork to velcro on top