Red Triangle On Screen

I keep encountering this issue where there is a red triangle that will appear in the last location of my mouse. It will move whenever I open any sort of menu, like pause, open a chest, ect. I'm using a custom texture packs but it used to happen with one I got from the marketplace if I remember correctly. Interestingly. this happens on every world and server EXCEPT for The Hive. I was wondering if there was a way to fix it?