Jupytext corrupts original notebook with base64 of pair

[EduardDurech]

I saw this issue may be related to jupyter-collaboration interacting with jupytext jupyterlab/jupyter-collaboration#214, but for some reason it will overwrite the original file with a base64 encoded version of the paired file. This is really bad as while code is recoverable, none of the visuals are

It also gives this error even though there are no other instances open, even duplicating the file and opening it for the first time will give the error

[mwouts]

Thanks @EduardDurech for following up on this.

I have added a comment on the Jupyter-collaboration issue: jupyterlab/jupyter-collaboration#214 (comment).

If you don't mind, we can continue the conversation there, or on the other issue #1124.

Kind regards