White dots appearing between blocks with a specific ressourcepack

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Hi there !**
There's a question i have since a few weeks... I'm trying to merge 2 of the ressourcepacks of my datapack minigame server... It works, but when i wear it, a lot of white dots are mooving around on blocks lines, it is very visible on dark blocks like black concrete. I tried to find the responsable files, and i just found than the more i have textures, the more i have dots. I suppose it's a size pack problem then... Once merged, the pack has a weight of ~515 Mo. There are 629 files in the textures file and the max texture size i have are a bit of 2048x2048.
Anyone has the same issue and know how to reduce/fix it ? If i can't find, i'll just stay on 2 separate packs.
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