the grass change the color when I walk in the savana

This is a known OptiFine bug. Turning off Dynamic Lightning should fix the issue. Please note that the Bug Tracker is only for Vanilla Minecraft bugs, not third-party ones.

the same bug without Optifine

Thank you for your report!
However, this issue is Invalid.

Your game, launcher or server is modified.
If you can reproduce the issue in a vanilla environment, please recreate the issue.

• Any non-standard client/server/launcher build needs to be taken up with the appropriate team, not Mojang.

• A world which had previously been opened with a modified client might be corrupted. Please try reproducing the issue in a newly generated world.

• Any plugin issues need to be addressed to the creator of the plugin or resource pack.

• If you have problems on large servers like Hypixel, please contact them first as they run modified server software.

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