key remapping

[Max <maxim.suraev@xxxxxxxxxxxxxxxxxxx>]

Hi all.

I'd like to change some of the w3m keybindings to those I'm used to but I would liek
to preserve defaults for the rest of them.

How do I do that? Searching for that revealed few receipts but none seems to actually
work :(

For example - how do I make use of
- backspace to go to previous page
- mouse middle-click to open the link in new tab

best regards,
Max.