VSCode always could have multiple windows. You can open multiple projects and they all share the same process(es), so clearly Electron supports multiple windows

VSCode always could have multiple windows. You can open multiple projects and they all share the same process(es), so clearly Electron supports multiple windows. What it couldn't do, though, was to have a single workspace span multiple windows (ie "detach" tabs). Whether or not this was caused by an electron limitation or a design flaw in VSCode, I can't say. Though I find it hard to believe that it would have been impossible to implement had they really wanted to.