For those getting black screen with Amazon Prime Video - set the speed to what you want and disable the controller overlay and it'll work right away. You can use the shortcuts instead as well. In settings, you can permanently disable controller overlay by default.

The extension is great and works flawlessly, the problem is that it renders a LOT of website completely unusable for upwards to 10-15 seconds at times. Whenever I open a link in a new tab, the website freezes for some seconds, on heavier websites the slow down is extremely evident. I just can't justify the performance loss. This does not happen with the same extension on Chrome.

There is significant slowdown to my browser when this is turned on. But the functionality works on videos.

This thing is reliable and easy to use, and it even is able to remember its settings when I sign into Firefox on another device so I don't even have to set it up again! Amazing

One of the few extensions i NEED for browsing. Only downside is it doesn't work on a few sites like google drive for example

Love this add-on. I watch most things at 1.2 speed and commercials at as fast as I can get them before they are over.
Currently (June 2025) I had to turn it off for Amazon Prime Video. With it on I only got audio on Prime Video, no picture. Turned it off and the picture works. Amazon Prime Video is the only streaming service I had this problem with, works perfect for YouTube, Peacock, Disney+, etc.

I really liked this add-on! To begin with, it works better than YouTube’s built-in player. The controls are minimalistic and disappear when not in use, so they don’t obstruct your view and everything stays simple; and best of all, it runs smoothly. I’ve only tried it on a few YouTube videos, which is exactly what I wanted it for: watching videos at three times the speed and it accomplishes that perfectly. Thank you so much! :D

This video speed controller is an incredibly useful tool! I love that it lets me speed up videos even where the UI doesn't natively offer it, saving me from using the developer console.

The only feature I'm really missing is a blacklist option to specify sites where it shouldn't activate. Currently, it interferes with my React development environment, causing issues. Adding a blacklist would make this extension perfect.

Controller is displayed in the middle of the Netflix videos.

Excellent and very customizable. Works on most websites with video, making it universal (unlike extensions for specific site only, e.g. YouTube). Can configure keyboard shortcuts as well as speed jump increments.

There is currently an issue where video playback does not display correctly on Amazon Prime Video.
However, this is still an excellent plugin.

The issue originates from the original Video Speed Controller by igrigorik, which this fork is based on.
I believe that codebicycle will address it once the original is updated.

In the meantime, the issue is being discussed in issue #1186 on igrigorik's GitHub, and a temporary workaround is known:

```
▶️ While the video is playing, press V

✅ The controller overlay will be removed and video playback will resume as expected.
```

Since 2025-05-03, With this add-on, Amazon Prime Video can't work. I.e. Sound is OK. but Image keep black screen.
This problem happens on Chrome too.
And it looks that other speed control add-ons don't have this problem.

Please solve this problem.

Suddenly on 4th May it stopped working on Amazon Prime. Whenever the extension is enabled, prime video shows black screen

Periodically completely kills performance on websites that don't even have a video in them. At least there's a blacklist feature.