How to buffer the entirety of a YouTube video

[K4sum1]

This is useful if you sometimes have a spotty connection and want a video to just be buffered. It only works for Firefox though.

Step 1: Go to about:config
Step 2: Search mediasource
Step 3: Change everything to false
Step 4: Search media.cache
Step 5: Change everything to 999999
You'll need to reload the tab, but your videos will now buffer as fast as your connection can handle.