Furfsky hogging up cpu

[SamTheWatermelon]

So I have been using furfsky reborn for a long time now. When I got on today, I noticed that every time I went into a menu such as the community shop or my menu, my cpu fan would get really loud. After a while of searching for possible causes, I turned to furfsky reborn. I turned off the "custom items" setting and my cpu fans did not act up again. I really like having a texture pack, and was wondering what may be the cause of this. I use badlion, so maybe something to do with that?

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