Remember users' manually collapsing of comments so revisiting doesn't require them to do it again
Also so refreshing does not reset the comment section state.
Could possibly also have a setting to automatically uncollapse comment threads when a new comment in that thread is made.
Also requested again recently here:
https://tildes.net/~tildes/15r7/if_you_would_like_to_add_a_feature_to_tildes_what_would_you_recommend#comment-806n
Edited by cfabbro