Do you fix bugs that appeared after a Magento upgrade?

Absolutely, post-upgrade breakage is one of our most common tickets. After a 2.4.x upgrade you often see DI compile errors, deprecated extensions throwing fatals, layout XML that no longer matches the new templates, or checkout regressions. We diff what changed, fix the incompatible code or extension, and add regression checks. While we’re in there we can also flag performance wins, see Magento 2 performance optimization. For multi-store or larger fixes we coordinate with the broader emergency e-commerce bug fixing service.