[Mikendebbie]

I am betting the chip is from a screw tip that was over-driven a smidge and it penetrated your fiberglass shower wall. Just a theory because I have a spot that is about 5’ off the floor on the outside wall toward the back and it looks like the tip of a screw. Mine has not popped yet...but maybe some day.

I have a white automotive touch up pen for my truck that might work but not sure I could get that approved by the review committee (DW)...and if it did not match...nope - I just talked myself out of that idea!