One of my favorite extensions is vimium. It enables vim like navigation on web browsers. If you press ? It brings up a menu showing all the key bindings, it’s very helpful. Adding that and a hotkey highlighter would be a good way to document such programs. It’s too bad that sort of thing isnt a priority
I will say my Fairphone is a good bit thicker than my work Iphone but honestly it’s not a significant downside for me. The weight is a bigger deal but still not worth the trade-off for a phone I can be confident I can repair myself