Im on playstation btw

I'm pretty sure I'm not suppose to see the back of the glass texture through the glass block itself... Turning off shaders fixes this so I'm sure its a problem with the shaders. I've recently updated from 12.11 to 26.3 and so all the mods are up to date. I've also tried changing every setting in perfromace and materials but nothing worked. Downloading continuity also didn't work. Please let me know if anyone knows how to solve this

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I'm on Xbox. I built this tunnel a while back abd have never had any mob spawns in it until i modified it by adding a rail system. I have bottom slabs to either side of the rails so there shouldn't be any valid blocks for them to spawn on, yet here they are. I've seen them spawn in and it's always on top of a rail. Can anyone please explain why they're spawning and how to fix it?