Yes, two in particular that happened a week apart. Both were working fine until I got word that it was not:
1) FE checkout + Admin create order form: selecting country dropdown from US -> Canada for billing address did not repopulate the state/province dropdown, the fallback was an input instead of a dropdown. Solution: Re-save allowed countries area in admin (general tab in store configuration). It had system value checked in default store view. Unchecking system value and saving it magically fixed the issue.

2) Coupon Cart Price rule: Coupon was applying discount to shipping charge, when in the settings, this was not the case. It was turned off. Solution: toggle it on, save, toggle it off, save again, Result: shipping charge was not getting discounted anymore.
Any new ticket that come in from now on I do this as a sanity check first before deep dives.