Rated 5 out of 5 stars

by Patuta on Sept. 25, 2017 ·

I absolutely rely on keyconfig. It's great.
Pleeaaaasssse make it work for FF57!!!

This review is for a previous version of the add-on (2016.2). 

by trlkly (Developer) on Sept. 25, 2017 ·

There's just really an equivalent API in WebExtensions, as far as I know. It's possible to replicate some of the functionality, but it would work completely differently, even from a user's perspective.

We do plan to keep it working for as long as XUL is available. Modifications necessary to keep it working with latest Thunderbird are planned. And It will continue to work with Firefox ESR until the user switches to version 61.

I would suggest that you look for addons that can replicate the features you enjoy, switching over to Firefox ESR to buy you more time. There is also SeaMonkey and Pale Moon which are maintaining XUL support.

There are definitely addons that will allow you to add new shortcuts in a page context. I don't know about replacing the ones built into Firefox, though.