Invalidating the caches of every single post a user has made every time they post a new reply or change their avatar would be a performance degradation but I’m not sure how much of one (also one which would obviously get worse the more time that goes by and the larger the forum becomes). Clover would have to investigate. It’s possible we could reduce the expiry time on the caches to make them update much sooner - maybe let them be a few minutes out at most - but I’m not sure how much impact that would have, either.