invalid "Transformation file URL" should throw an error

[synox]

I don't like the behavior when having a typo in the url.

Expected Behaviour

It should show an error: "Tranformation file not found"

Actual Behaviour

An import it run with the default config, and overrides any existing word documents.

[kptdobe]

No import file is a valid use case ("default import") and you can easily see in the console log that the file cannot be found (red 404 error).
Maybe simply showing a message like "No transformation file found, using the default one" to inform the user could be a good compromise.

[atopper]

I've heard this from different people myself, that a misspelling of the transformation file has lead them astray.
I suggest a little subtle note (not a toast as they might miss it). Something like this which might be shown if the file can't be loaded and checked when the input is changed or when the "Import" button is pressed: