opengl error 1282 invalid operation in chat, got lots of mods and idk which is effecting or where to chrck for logs etc

Sounds like #206

solution is a lot harder to do, as i have 200+ mods, no crashing, the portal loads, i can still walk through with no loading screen, the only issue is that the portal itself isnt seethrough as its meant to be, the obsidian on the inside where the actual portal is is red, the error spams in chat when looking at the portal but when far away it stops

I've also removed CoroUtil and Weathers2 and the issue still persists, only sounds go through from the end portal, and then u could see like entities, such as the end crystals, item drops, and mobs, optifine isnt the issue either, fast render has been off, here is an updated debug log I can't find anything that stands out, so far I've removed coroutil, torohealth, and weathers2
debug.log

happens with aether too, u can barely see the other side but can definitely make out the islands

Ah, it's not the same issue anyway then, the completely white screen (on rare occasion different color) is a distinct part of that issue which I've had multiple reports of.

Please you attach the log of your game after you've looked at a portal and reproduced the issue. It's usually named latest.log (or preferably debug.log if it exists) in the logs folder inside your .minecraft folder. Given the size of your mod pack, it should be on the order of thousands of lines and also mention that error 1282, otherwise you've likely got the wrong file. Maybe there's something interesting in there or at least I'll then know which specific mods you're using and maybe I recognize some of them.
Also, just to make sure: You do not have Optifine's Shaders enabled, correct? Cause if you did, then that'd be expected behavior (the portal being non-see-through part, not the error but idk what OF does so there's little chance I could fix the error in that case).

I've removed all mods all at once and had just BP on and it worked just fine, put them back and it stopped working, then removed Optifine to see if it was the case, but no fix, didn't have shaders on either, removing Optifine only stopped the error comign up in chat but the portal itself not working at all times. Here's a log with all mods, including Optifine. I've removed a mod called ToroHealth, as it was being listed in the log error, it now sort of works, i can see items and somewhat entities at a standstill from the nether side but there is still this weird look to it shown in the screenshot
is this maybe optifine?
the error is also still going on
debug.log

It works perfectly now, I've removed all the mods listed above, I had valkyrienskies removed already yesterday but i removed Albedo, MovingWorld and DavinciVessels, and nether portal fix, and its workin just fine now

Great.

Can I bother you to test specifically which one of those causes the issue?
If it's MovingWorlds/DavinciVessels it'd like to eventually fix the issue, if it's NetherPortalFix, I'd like it to fail fast with a useful error message.

Added back MovingWorlds and DavinciVessels, worked just fine, then added back Albedo and it went back to the same error and problem. Seems Albedo is the issue, didn't test out NetherPortalFix though

The mods which to me seem particularly likely to cause this are:

• Albedo: has multiple severe bugs (unrelated to BP), I've tried to report those to them but #120 (comment)
• MovingWorld/DavincisVessels: High chance of conflicts because it touches chunk rendering
• Valkyrien Skies: Used to hard-crash prior to its 1.0 version, haven't yet seen anyone run it with BP; also high chance of conflicts because it touches rendering and collisions
• Nether Portal Fix: High chance of conflict because it touches nether portals; doesn't even do anything which BP doesn't already do by itself

If it's none of those, then the simplest way to narrow this down would be to throw out half the mods, re-test and continue with whichever half didn't work until only conflicting mods are left.

I see you've got Mekanism installed, might be interesting to see if same-world portals (BP supports Mekanism's Teleporter) behave any different.