The simpliest WebExtension that introduces Emacs-like navigation keystrokes for all web-pages. Tested with Chrome 61 and Firefox 57.
The keystrokes supported so far:
C-p - scroll step up C-n - scroll step down C-f - scroll step right C-b - scroll step left M-< - scroll to top M-> - scroll to bottom C-v - page down M-v - page up C-x, f - open a new tab C-x, k - close the current tab
Scrolling step is dynamic and depends on the height/width of the current window. It's supposed to scroll the size of the visible document area in 5 steps.
The software is licensed under GPL 2.0 license.