Stage View is missing after Plugin update

We're running two legacy Jenkins servers, one running the old 2.9, the other the slightly newer 2.10 version. Due to plugin version mismatches, the stage step plugin on one server would constantly nag that we don't use

stage('Stage 1'){ }

arguments with a block. To get rid of that, we've updated both the Stage Step and Stage View plugin to 2.2 on both Jenkins servers.

But now an even worse problem occurred, our pipeline stage view is simply invisible (see attachment).

Were there any other plugins we needed to update? Too many projects depend on the reliability of the Jenkins, so we would rather not have to do a complete update and potentially fix a million things.