Immersive Portals Mod For 1.19 / 1.20.+

Immersive portals is an incredible and game-changing mod. It cuts out the annoying loading screen when you're about to travel to a new dimension; now, you can go through portals seamlessly and see the other dimension through the portal, which is bizarre. 

This brief effect applies to any portal, but I'm not sure about foreign mods' portals, I didn't test it yet, so there's no harm in giving it a try.

Immersive Portals mod doesn't work with OptiFine, but you could use the Iris shader mod with Sodium to get the same features, and it will also allow you to use it along shaders! Please take into account that the Immersive Portals mod isn't fully compatible with shaders, so it's better to use the mod without it; it could also get very laggy due to the mod's effect mixed with the realistic visuals of the shaders.