There's an incredibly useful extension that's not on that list that I bet a good number of HN folks would like:

Vimium [1]

It lets you use keyboard shortcuts to navigate through webpages, click buttons, jump to text boxes, etc. it's been huge for me both as a productivity tool (it's significantly faster than using a mouse for navigation) and also for reducing RSI/strain on my hands.

Here's a video of it in action as you really need to see it being used to understand the different interaction model it provides.

https://youtu.be/t67Sn0RGK54?t=21

1 - https://chrome.google.com/webstore/detail/vimium/dbepggeogba...

edit: fixed link (but if you enjoyed the writeup of data security requirements let me know).