First of all thanks for leaving a review, it means a lot!

1. Keypad: I personally like the idea, but it won't work for people with notebooks that don't have the keypad (including all MacBook Pro's) or tenkeyless keyboards. Additionally, the Firefox API won't even allow me to map to they keypad AFAIK, unless it's not documented.

2. Rearranging containers: this sucks for me too, I hope Firefox implements this feature soon! Implementing it into this extension seamlessly might not even be possible with the current Firefox API – i.e. without losing the session information on existing containers, plus the UI would have to be different than the native container UI. Additionally, it's not a feature that would "fit" this extension, which is meant to be a super-simple extension... But again: I understand your pain, I have it too :)

3. This extension is open-source! If you're a developer feel free to contribute, the code-base is really simple (see the website link on the extension page).

Till next time!