When adding reactions to PR comments, "thumbsup" and "+1" are considered separate reactions despite being visually the same. This results in weird situations where you can see two separate reactions instead of one since some people use one over the other. (And in some cases, people just click an existing comment reaction or select from their "last used" reaction list, which can cause this problem if just one team member uses a different reaction from the other team members.)

"thumbsup" and "+1" show up as separate reactions in at least the following places:

1. Reactions on PR comments
2. Options in the reaction picker

The attached image shows a PR comment with two "thumbsup" reactions and one "+1" reaction.

From a quick look, it seems like there's a similar problem with "thumbsdown" and "-1".