Create an option that allows user to click/select the element to accelerate and to manipulate its speed, similar to how the adguard select element to block works:
- right click element:

2. instead of block ads (like in this example) have an icon called "manipulate speed"
- right click and toggle the element size to find the speed control
There is (mostly) always some html code that can be manipulated it just needs to be found and plugged into the right place