I have this task I don't usually write down, but let's do it: periodically (usually once a cycle), check through the tests for obsolete conditionals or workarounds - things we introduced for bugs that were fixed, or releases that are now EOL, or whatever. I usually do this by searching for EOL release numbers, and the string 'FIXME' (which I try to always include when introducing changes that are likely to be time-limited).