Grow the checker
Every problem I find by hand becomes a rule and a test page the same day.
Note
Notes are where things go before they turn into a case study. Some never do, and that’s fine.
When I find a problem by hand, I fix it, then I add a rule to the checker and a small test page that shows the problem.
The test page proves the rule catches it, and stays as a guard so a later change can't quietly undo it.
It's the cheapest QA habit I have. The checker now knows everything every reviewer has ever told me.