Did you try the Fx DevEdition? I know of some recent Source Map related changes. If the issue persists (same with the other issues you mention), would you mind filing a bug [1]?
[1] https://bugzilla.mozilla.org/enter_bug.cgi?product=Firefox&c...
Yup, I tried FF Dev Edition a month ago, same thing. Maybe I will try again later after updating
Some examples:
- debugging with source maps: it doesn't work properly (I can set breakpoints and debug variables content on typescript files in Chrome, but not in FF)
- JS exceptions: clicking on the filename inside the stack opens a new window with the source of the JS file, not the debugger (ugh)
- doesn't support typescript highlighting