Rated 1 out of 5 stars

No es tan importante, para eso existe panorama.

This review is for a previous version of the add-on (2.0.2011062701.1-signed.1-signed). 

Different purposes

Fox Splitter and Panorama have different purpose for each. For example, if I translate a page of MDN (Mozilla Developer Network) from English to Japanese, I want to compare the translating version with the original English version. Fox Splitter is designed for such a case, so it has a feature "sync scroll". This can't be done by Panorama. Instead, Panorama is more useful than Fox Splitter to view all tabs with their screenshots.