Works Rated 5 out of 5 stars

Does the job very well.

Imported my OPML with over hundreds of feed just fine (a little slow, but that's understandable).

Export is a lot faster, the extension manages to export my aforementioned collection of feed in under a minute.

The exported OPML file look valid. I've successfully import it into other feedreader (Liferea).

This review is for a previous version of the add-on (1.6.1-signed.1-signed).