Entities that use material state "Blending" still not render correctly if the are rendered on the edge of the transparent block

Bugreport
In 1.16.210 there was the following bug fixed
"Entities that use material state "Blending" now render correctly behind transparent parts"

However after testing in game, the entities still render incorrectly if the player looks through the side of the block. You can see this with end portal tiles, they will render and flicker through the edges of a glass block

How to reproduce it
Make an end portal, like one in the video, and then place a glass block above it.

Expected result
The portal block should be rendered correctly over the whole block and not only in the middle of the block

Media
In the video you will see that if the player looks through the side of the glass blocks, the end tile will flicker. But if stand directly above it, everything is rendered normally. This is what was fixed in 1.16.210

The picture will show you a placed end tile with the `/setblock ~~~ end_portal` command. You'll see the end tile renders in front of the glass block, while this shouldn't happen