[pythonaut_16]

I doubt the author would make the same complaint if Microsoft wrote similar proprietary extensions for Emacs or Vim or Atom.

I also doubt they would make the same complaint if JetBrains or someone else wrote the same proprietary extension for VS Code.

Neither the first case nor the second would make any of those editors any less open source.

[codemonkey-zeta]

If Microsoft wrote a proprietary extension to emacs that was so compelling many would consider it to be the "best" feature, I think devs would complain. Emacs is way more FOSS than VScode claims to be, so that would be an even worse affront to the philosophy of the editor and community. Maybe you're right about the JetBrains products, but to my knowledge they don't market themselves as open-source to the extent that VScode does.