Works amazingly in 95% of cases. The 5% of cases it doesn't work in are YouTube and Twitch streams (it will constantly try to skip ahead if there's dead air but since it's live, the audio just sounds like the stream is skipping a bunch). If you could blacklist specific sites to not run it on(kinda like how uBlock Origin does) the issue with Twitch would be fixed, not sure how YouTube live streams could be handled though. I'd assume YouTube uses the same video player for both streams/videos so differentiating between a stream and video may be impossible for the developer but idk.

EDIT: It seems the developer is aware of people wanting to blacklist sites as there have been suggestions for this feature on the extension's repo; however, it seems that Firefox makes it more complicated to do than Chrome.

Request new feature: Smoothed playback dynamic acceleration


Example :

1- set desired speed *e.g. x3

2- select starting speed *e.g. x1.5

3- % of video passed until desired speed is reach e.g. *60%

Result:

The video begins at x1.5

increases gradually as a function of time based on the duration of the video

by 60%, speed had gradually increased from 1.5x to 3x in 0.01 stepsizes.

e.g. at 60% of elapsed video duration it will be

playbackRate = x1.5 + (x3 - x1.5) * (currentTime / duration) / 0.6

This formula means that the playback rate will start at x1.5 and increase linearly as a function of the current time divided by the duration of the video until it reaches 60% of the duration, where it will reach x3.

This passive increase in cognitive load will lead to increased comprehension.