If the player enters the crawling/swimming animation while on top of glass, while in 2nd/3rd person perspective, the glass is ignored by the camera. Even the lines that around each glass block are not visible (like in spectator mode). Attached are two video files, one showing with solid blocks, and the other with glass. I do not know if this is intentional behavior, but it is not the case in 1.15.2

Edit: The player doesn't have to enter the crawling animation. The attached pictures (from 20w16a) show that glass is ignored from just the standing position. Also that a wall of glass has similar results. And going back through the versions I have noticed this started happening in the 20w12a snaphot. And as a side-note, this also is the case with glass panes and any colour of glass/pane.