Superb! Very useful add-on!
I hope that it continues to be developed. For example, to be able to drag it with no restriction. Or to have multiple pages that you can switch.

Awesome extension! Exactly what I was looking for to watch my email.
Add more futures plz
- open in a new tab not in mobile view
- back button
- multiple side views
- resizable more then 1/3 of a page

I use it to keep my task lists open alongside my email+calendar+etc, so it's really a huge help with my daily office work!

Fantástica extensión realmente práctica. Yo añadiría la opción de mostrar la versión de escritorio de las webs en el Sidebar y no solo la versión móvil.

This is an amazing idea and a very handy one. It should be not just developed but considered a Firefox essential piece.
It's great for web-mail checking, mobile version view, quick service checking, rapid social media posting, etc.
Hope it gets the attention it deserves.
Thanks a lot for such a great add-on!

great productivity booster!

This is a great Addon. So far so good.
Feedback
In any YouTube video, I can't find horizontal scroll bar. Also there are two huge horizontal black bar. (What I'm trying to say is that the Addon is unable to adjust according to the video's aspect ratio.
Again, great Addon.