[testestx]

> If you do not wish to give them the rights to your modifications, the license forbids you from using it

Unless your use qualifies as fair use

[alok-g]

In my observations, "fair use" is often misunderstood. People violate copyrights thinking theirs is a fair use when it's not.

[detaro]

Is "fair use" on software even a thing?

(I know some jurisdictions have basic exceptions like "if you own software you can do what's needed to run it", but modifications?)