Media Items in JSQMessageViewController's Collection cells are not showing in IOS 14

You need to overwrite in JSQMessagesMediaViewBubbleImageMasker.m
method - (void)jsq_maskView:(UIView *)view withImage:(UIImage *)image and change line:

view.layer.mask = imageViewMask.layer;

to be

view.maskView = imageViewMask;

I suggest you to use category for that. For me that was solution.