What i like about this one is the fact it can use your bookmark. With other similar addons you need to create a separate account to keep your dials, with this one you only need your firefox sync account.
Another thing is that i consider it ugly by default with lacking customization options from the GUI. However thankfully it allows to add your own CSS to customize it completely. This way i managed to do a dark theme i actually like. Good job and please, keep developing it.
Here's the CSS i made in case someone want to try:
