When it's windy, grass and tall grass blow in the wind. But when you break them, their particles are purple/black indicating missing particle texture. I couldn't fix this with a resource pack like I usually do.
EDIT: it's the plant shader option in advanced options. When it's on, plants have missing particle textures.

1.12.2 probably won't be supported here considering 1.18.2 just came out. Can you try the 1.18 update? 😃

Unfortunately no, I can't use 1.18 which is why I'm posting about a 1.12.2 issue. I hope bug fixes can still be done on it, considering how many people are still using it. Updating to a newer version is not always possible, some mods are only for 1.12 and will remain there indefinitely.

For those using 1.12 then, you may go to Mrbt0907's fork and try that one. If you have any issues please let us know over there ^^

Oh, I actually did switch to it. I switched after posting the bug report though. I may have to report some bugs there as well.

Yeah go ahead, I'll be sure they're seen^^ enjoy the mod!

Oh also I forgot, if switching resolved this issue here you may close this issue, there's a truck load of issues open with this mod and I couldn't reproduce your issue here so I'm assuming it's a openGL bug for you in 1.12.2 weather2*