> I personally don't have a problem with the general ability to change vendor code. The question is whether you want it in an specific case or not. If you update frequently then certainly not. But that decision should be deliberate team policy.

Fair, in the instances I ran into it was code that was downloaded and unzipped into a "js-library-name" folder but then the code was edited, even worse, the `.min.js` version wasn't touched, just the original one which led to some fun when someone "helpfully" switched to the min versions that didn't have the edit. IMHO, if you want to edit a library then you should be forking and/or making it super obvious that this is not "stock" library X. We also ran into issues with "just updated library Y" and only later realizing someone had modified the older version.

But yes, if it's deliberate and obvious then I don't have an issue modifying, just as long as the team understands it's "their" code now and there is no clean upgrade path in the future.