Explaining the problem more in-depth than the titular definition:
Often I merge branches into master and want to prune based on that.
M-p works fantastic for removing the remote branches (eg
origin/mergedbranch) but not the local branch (eg
mergedbranch) that referenced it before. I'm left with branches like the in the screenshot below.
There seem to be a lot of cli git commands such as this SO answer, but I was wondering if there was a magit equivalent.