Yes, PyLance has a pretty strict license and makes it very clear it cannot be used in forks (and that's not really surprising and pretty standard I'd even say for a corporation such as Microsoft, it's like the current licenses saying this is open source but cannot be used by competitors, what's really surprising for me is that forks are choosing to ignore this):

> INSTALLATION AND USE RIGHTS. a) General. You may install and use any number of copies of the software only with Microsoft Visual Studio, Visual Studio for Mac, Visual Studio Code, Azure DevOps, Team Foundation Server, and successor Microsoft products and services (collectively, the “Visual Studio Products and Services”) to develop and test your applications. b) Third Party Components. The software may include third party components with separate legal notices or governed by other agreements, as may be described in the ThirdPartyNotices file(s) accompanying the software.

One thing I don't understand is how forks (I'm actually talking about Cursor which is one I'm actually evaluatinng) are getting away with scrapping all extensions from the VSCode marketplace... I even e-mailed them but had no official position on that. Maybe they have some separate contract with Microsoft -- they do have OpenAI backing, so, maybe they have some bridge there, does anyone know? Or maybe Microsoft is just waiting to see how they themselves can profit for it and so is taking no legal action at this point?

-- disclaimer: I'm on the author of PyDev and I do have my own Python extension that I publish to VSCode and OpenVSX (https://marketplace.visualstudio.com/items?itemName=fabioz.v...)... it's completely Open Source in Eclipse, but for VSCode it's currently commercial. I discovered that's a nice way to have less people requesting support, even though 99% of it is still Open Source ;)