it does have some errors in chat but im not sure how to fix them
ver 1.12.2 mods optifine
legacy shader
macos

Sorry. I can't support macOS, but will leave the topic open if anyone has any idea what the problem is. It is a problem that only happens on Macs. I don't have a Mac and I don't have the time to look for one and run tests. Sorry.

If you have programming experience, you can try to analyze the code of the programs that the chat mentions on the Mac. You can comment out lines that are potentially causing the problem. It is the advice that I can give you to try to find the error yourself.

MacOS causes a LOT of problems with the video drivers and their OpenGL support. I am 99% sure it is a problem with the video drivers.

The problem with "clouds" is new to me, but I suppose they are related. Although I suppose you could avoid it by deactivating the volumetric clouds.

For other occasions, I recommend, before submitting a report, fill in ALL the necessary information to reproduce the error. Specify:

• Minecraft version.
• Version of the Shader (only the last one at that moment will be taken into account).
• Check if the problem happens with Minecraft WITHOUT mods and with the default resource pack. If not, INDICATE which mod or resource pack causes the problem.
• Indicate what steps must be followed to launch the error.

Otherwise it is practically impossible to find out what the cause is. Thank you, and really sorry.