Consider adding a button to the status bar to switch the current file mode

[zzhaolei]

Like this button, it can be toggled by clicking with the mouse.

[mossgowild]

I'm waiting for the official read-only feature, depending on this feature I'll decide whether continue to develop this extension, see microsoft/vscode#4873.

[zzhaolei]

Now vscode supported readonly, maybe we can improve this extension on this basis, because vscode does not have outOfWorkspace and reader mode