Since updating to Revit 2021, I've run into an issue relative to elevation views with "Realistic" Visual Style selected. The glass of window and door families appears transparent when hosted in angled or curved walls. If the host wall is aligned orthogonally to the elevation view, then the glass appears opaque as it should. It would be great if the glass in these instances could have a consistent appearance regardless of whether the host wall is angled or orthogonal, much like in previous versions of Revit.
There are workarounds for this issue, though they can be somewhat time consuming and not very straight forward. In my opinion, this is not something that Revit users should have to fix with workarounds. I quickly became a fan of the new "Realistic" Visual Style appearance that comes with 2021 (once I familiarized myself with all of the new settings), though this issue defeats the purpose of using a style that should appear realistic.