one-time install
npm install -f @vscode/vsce
cd ~/git/vscode-jupytext/
vsce package -o vscode-jupytext.vsix --no-yarn
from https://code.visualstudio.com/api/working-with-extensions/publishing-extension#packaging-extensions
code --install-extension vscode-jupytext.vsix
from https://code.visualstudio.com/docs/editor/extension-marketplace#_install-from-a-vsix
NOT using the azure devops pipeline, but publishing on open-vsx.org instead see https://github.com/eclipse/openvsx/wiki/Publishing-Extensions
npx ovsx publish vscode-jupytext.vsix -p <token>