Add A Like Dislike Bar To YouTube Video Thumbnails In Firefox

One annoying restriction on YouTube is the lack of information displayed on video thumbnails to help you decide which one is worth watching next.

The thumbnails on both Search pages and the ‘related’ content Suggestions (on the right hand side) only display the number of views, not the proportion (or percentage) of likes compared to dislikes.

Only after you have clicked on a particular video to view do you get to see the number of likes and dislikes for it – these are a far better indicator of a video’s quality and usefulness than the number of views alone.

Janus is an add-on for Firefox to save time and avoid clicking on useless videos by adding a like/dislike bar underneath each YouTube video thumbnail – this bar is color coded for green (likes) and red (dislikes) so you can immediately see the proportion of likes compared to dislikes and avoid clicking on junk or fake videos.

You can also set Janus to hide thumbnails for poorly rated videos, and completely remove thumbnails for really poorly rated videos. Hiding useless video thumbnails frees up space on screen so you can see more thumbnails on the page and it makes choosing higher quality videos even easier.

An example screenshot of Janus showing the added bars is below – note how the thumbnails of 3 videos are hidden as they are almost universally disliked, despite having over 15 million (wasted) views between them:

Janus like/dislike bars in action

Using Janus – Download from Mozilla Add-ons here. After installing you may wish to configure the Options for this add-on. As shown below, you can choose what % of dislikes qualifies as “poor” and “really poor” and whether to hide or remove those thumbnails – by default they are set to 60% and 80% respectively.


You can also set a minimum on the number of votes a video must have before Janus can hide or remove it automatically. This threshold level is designed to prevent a few early dislike votes from hiding a video thumbnail that may actually be high quality but has only just been released.

The add-on keeps track of ratings info as it fetches, so it doesn’t need to re-fetch the same info – this allows it to display the same ratings bar immediately.


Janus is a neat add-on for Firefox to display, in a simple pictorial view, how well liked videos are – before you waste time clicking on them. It can also hide or remove videos which are clearly junk, depending on a threshold which you can configure.

Relying just on the number of views is not enough to eliminate fake and useless videos. Being able to see how well liked they are, in advance, is a welcome addition to YouTube browsing – it should really be a standard YouTube feature…