I have acrylic
(plexiglass) windows in my H26. Getting anything to bond and stay that way is a problem. The factory adhesive
is failing and I've been removing, cleaning
up, and replacing the plexiglass one piece at a time. There are a few specific silicone adhesives that are supposed to work best, but they are not clear.
While on the last window I did, I "saved" the original plexiglass and just replaced the caulk, I won't try that again as it was extra work and there was some inevitable crazing from the handling. If you can provide the old window as a pattern it is affordable and straightforward to get a plastic place to duplicate it including any curves, bevels, tint, etc., I would have paid probably $150 for a 60" long window. Would have been worth it.
, if you have cracks and chips, would be to either live with them or replace the plastic.