I would like to record browser animations in the smoothest possible framerate, including an alpha channel. Due to single threaded performance limitations I am looking for a way to slow down the producer of these animations. I currently achieve this by increasing the delay and duration of timers (in my case anime.js), this allows me to sample screen at a lower frame rate, while the target frame rate can be achieved.

The change of duration and delays is not overly painful, but I would like to do this in a more generic way. For example instruct the browser to have a world clock that runs on 10% of real speed. I have already found the Proxy suggestion below, but this does not seem to impact the current animation rendering. Slow down time with JavaScript

What can be done to globally reduce all the animation, as if everything would take 10 times longer?