LISTEN HERE GUYS: while this add-on does not work anymore (for now), consider visiting the official website and installing either the latest version OR using the userscript!

Till it is back working users can try addon Thumbnail Rating Bar for YouTube
it shows you likes and dislikes before even clicking on a video.

Everyone, the add-on is not working right now, but the fixed version is created - it just needs to pass Mozilla's review to be authorized. Give it some time.

Great addon, works every time. Currently waiting for the new update to be uproved by Firefox, so that the extention is functional again.

A great extension. People, please wait for the addon to be updated, it's mozilla you're waiting on as this is a "Recommended" addon and has to be approved by them. There's already and update that you can grab from the github and it works perfectly. The dev has already published the update, they've done all they can on their end.

Please stop downvoting because it stopped working. You can read. Youtube broke it-
Please wait till the author makes an update (if possible).

It's been working great until few days ago thanks to yt/goog. Hope the author would update this handy extension soon.

Solid, no-frills extension that returns what should still be a basic feature to YouTube.
Currently doesn't work, but that's because YouTube did yet another update trying to break stuff like this.
Hope this extension gets updated soon, but appreciate all you do either way.

Currently doesn't work :(

Love this plugin. It's been working without any issue until youtube ruined it all with a stupid update :L