How ever it happened ? does it matter. It cracks with age or impact, shrinks and expands with temps every year. Cut a piece out take to RV store to get the right size buy white or black your choice take a few minutes and replace the piece. Or measure it yourself and buy through the web. I have replaced some
on or all of the stuff on several RVs I owed and 2 truck canopies. If you just remove it and not replace it that is OK too, just looks unfinished. Without it you may get water in around the screw heads at some point.
2013 24RKSWE (27ft TT) Cougar 1/2 ton series
2013 Ford F350 4x4 CC 6.7 engine, 8 ft bed 3.55 rear end lariat package
Retired from Oregon State Police in 2011 than worked another 9.5 years as a small town traffic cop:
As of 05-2020, I am all done with 39 years total police work. No more uniforms for me.