If I open a diff window the first time in a project and it is a CSV file the CSV editor opens an empty window.
Afterwards I am not able to open any diff anymore - including other file types - the CSV diff always shows an empty file.
The only solution I found yet is restarting the project.

If I open a diff on another file first the basic diff window opens also on CSV files.

Honestly not sure if this an issue of that plugin but I think so (sorry if not).