Per the Github import process a LOT of branches ended up being created from closed branches in the original Mercurial repositories. Consider archiving them, then deleting it from the remote repository.
Take a look at this StackOverflow post for how to do so. As a quick standard, it might be worth renaming the tags to clearly signify it's an archived branch, e.g. archive-[name-of-branch]
Per the Github import process a LOT of branches ended up being created from closed branches in the original Mercurial repositories. Consider archiving them, then deleting it from the remote repository.
Take a look at this StackOverflow post for how to do so. As a quick standard, it might be worth renaming the tags to clearly signify it's an archived branch, e.g.
archive-[name-of-branch]
https://stackoverflow.com/questions/10242924/how-to-close-a-branch-without-removing-it-from-history-in-git
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