So it's a mix of here using the old way and the new Firefox breaking it, but not yet fully supporting the new way.
Isn't there a library that handles these things for you?
There are several, of varying qualities, of differing interfaces, and supporting different things. This is the awfully complicated patch option.
@Velocio started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
So it's a mix of here using the old way and the new Firefox breaking it, but not yet fully supporting the new way.
Isn't there a library that handles these things for you?