I think you are referring to this? From the wiki at https://github.com/microsoft/vscode/wiki/Keybinding-Issues:

    Are you customizing keyboard mappings via setxkbmap or equivalents?
    
    symptoms: customizations done via setxkbmap or equivalents have no effect in VS Code.
    
    solution: use "keyboard.dispatch": "keyCode" in your settings and restart VS Code.