A "minor update" refers to a small or insignificant change or improvement made to something. It is a simple modification that doesn't have a significant impact on the overall product or situation. Full definition
This multi utility vehicle has received minor updates in terms of almost every aspect. (cardekho.com)
These sound like relatively minor updates in the grand scheme of things, and yet they've still not been put in place. (indiegames.com)
Or rather, the company will not be pushing out any major update to this device, instead, only minor updates such as the current one will be pushed. (nashvillechatterclass.com)