That sounds like they legally released it under MIT. They legally can't just revoke a license grant, even completely unpublishing it by rewriting git history wouldn't solve that.
I want Microsoft to share the vscode extensions, but that reasoning seems weird to me. MS is hosting the extensions, they could decide what applications get access to them. But also saying anything published by mistake immediately makes it part of the current state of an open source project seems too violent. Software authors should decide the terms of their software, maybe past versions maintain the license included in them, but they are not eternal, should the author decide so.
If at some point I want to turn my application more commercial friendly by amending the license or changing it completely, and people tell me "No haha sorry you released as MIT at some point so it's now free forever mate" I would get pissed off and stray away from open source altogether. At least this is how the "you can't revoke a license" argument feels to me. But like I said, past versions that include a specific license should still be governed by that license.
> MS is hosting the extensions, they could decide what applications get access to them.
A better way to do that would be to add some trivial access protection (like a password they didn't accidentially publish). No matter how weak, any attempt to circumvent it would violate anti-hacking laws in most jurisdictions.
> "No haha sorry you released as MIT at some point so it's now free forever mate"
For you existing code that's exactly how it works. Otherwise the concept of licensing something becomes close to meaningless. Imagine Google releases Kubernetes as open source, you build your business on it, and suddenly Google turns around and says "just kidding, everyone who wants to use Kubernetes after next monday has to pay us absurd licensing fees". Using anything open source would be an insane risk if that was possible.
Instead what people usually do is to say "everything I do from now on is closed source. You can maintain a fork of the old version, but good luck keeping up with my version". Or alternatively "everything I do from now on is under [GPL/AGPL/similar restrictive license], if you want to use it beyond that contact me for a more permissive license deal". You can give people more permissions on things you own, or attach fewer permission to new things than you did in the past, but you can't take permissions you already gave away.
When something was obviously committed in error such as in this case (I say obviously because it is well documented that the URL's are not to be made public, and the commit was reverted quickly), I think it is in bad faith to take that mistake and use it against the company giving you the free product. Sure, it might be legally fine, but from an ethical standpoint (and even from a "lets not make OS sound so dangerous to companies that they never want to contribute again" standpoint), I personally don't think this is in good faith at all.
>Instead what people usually do is to say "everything I do from now on is closed source. You can maintain a fork of the old version, but good luck keeping up with my version". Or alternatively "everything I do from now on is under [GPL/AGPL/similar restrictive license], if you want to use it beyond that contact me for a more permissive license deal".
Yes this is what I was describing as reasonable. "Everything after this is governed by X terms" is reasonable. But the whole thing can sound like even if you change terms, previous licenses would still apply, which would be wrong.
To circle back to the specific case of the VSCode extension URLs, at the time they were "new stuff" they were published in a repository with an MIT license notice, effectively publishing them under MIT. For that version that license applies forever. If they change the URLs and keep the change proprietary that's fine, they just can't take back the past.
Though it should be added that I'm just expressing the common understanding, barely anything surrounding open source licenses was ever actually tested in court. There are also some obvious legal positions that would completely change this: does every change need to state the license, are open source licenses actually legally binding etc. However nobody would ever argue those positions because they are detrimental for everyone (ok, the latter one was once argued in a GPL trial, but the court decided not to decide on that)
