When connecting to Atlas free tier and looking at the performance tab, Compass shows an error (Command "currentOp" returned error "cannot do raw queries on admin in atlas") and the charts are empty.

The error goes away and the performance tab works normally after leaving and coming back to it.

durran.jordan took a quick look and it seems we have some legacy code there to support MongoDB 2.x which has been EOL-ed for a while. We can remove that logic and see if it solves the problem or what other error the server returns.