When code is stashed the pattern under stashes is On {BRANCH_NAME}: {STASH_NAME}. Generally the branch name is going to be longer than the side panel meaning if you are looking for a specifically named stash you have expand the panel and then collapse. It would make more sense for the stash name to be visible first because that's the more important information, not the branch it was stashed on.
Not sure if this is the right place for enhancement suggestions like this, but it was the best I could find.