How I rated the add-on:
Did the add-on work as you expected it to? Yes, the add-on is worth 5 stars.

However, anytime I use this add-on, Firefox starts to consume super-high RAM and becomes unresponsive for 5-10 minutes. If I forcefully close Firefox, I receive a browser crashed notification within the same amount of time. -2 stars (can get pretty inconvenient)

Just because I have this problem doesn't necessarily mean you will.

What features did I like or dislike? I like all features, and there is none I dislike.

Is it useful? Very useful add-on
Is it easy to use? It is easy to use.
Will I continue to use this add-on? For now.

Other notes:
Creating a new account elsewhere to make the creator aware of bugs is totally unnecessary. -2 stars

Creator is attentive and still reads reviews. +2 stars

Creator will try to fix issue if you're willing to make a GitHub account. +1 star (I'm not willing to)