Hi,

firefox 36.0 removed the "-remote" command line option, see
https://www.mozilla.org/en-US/firefox/36.0/releasenotes/

Unfortunately this breaks "browse-url-firefox" which depends on it. To
fix this, please apply the patch below.  I also put the patch on github
https://github.com/andram/emacs/commit/fd19dadba178f781117dfe524de834f337cbb1a6
not sure which is more convenient for devs, as I am not a regular
contributor.

Comment of patch: Patch now uses "--new-tab" and "--new-window" command
line args, which are supported since a long time.  This makes the
sentinel redundant.  It should in theory also work on MS-Windows, and
even improve the situation in that links can now also be opened in a new
tab if desired. However, I only tested the patch on linux.

Thanks
Andreas