On cooking.stackexchange, a user without the rep to propose a tag merge noticed that we don't need both the tags brining and brine. I first created a synonym proposal pointing from brining to brine. After that, I noticed that there is also a "merge" link (possibly a mod-only functionality) and used it, merging brine into brining, creating a synonym while doing so. I didn't remove the old proposal before that, because I didn't see a way to do it.
As a result of this, now we seem to have been left with brining as a synonym of brining, which is confusing at least (maybe it also has side effects, but we haven't noticed them yet). I think it would be good if this can be prevented from happening somehow, so the next hapless mod can't repeat my mistake.
The merge request is on Can we add the synonym [brine] for [brining]?