Trying to upload files freezes

Hi, Whenever I try to upload any sort of file, the file explorer pop up thing opens, and then freezes. This doesn't happen with any other application, just Firefox, and it happens across websites. Eventually the window freezes long enough that you get the 'close/wait to respond option', and then it closes. Firefox itself doesn't freeze, just the file picker. Nothing ever crashes/closes unexpectedly, and there's no crash reports in the about:crashes thing. It's not super urgent because you can copy and paste most files but it is frustrating. Any help would be very appreciated. Thank you