Noticed over on The Burning Edge that the latest Deer Park (Next Firefox) nightly build appears to have fixed the remaining regression bugs, not to mention the dozens of other bug/security/other fixes which have been included over the past few weeks. I’ve been using these nightlies myself for a good while without any major issues & as I may have mentioned before; the new Firefox will enable several features by default which we’ve covered in our Firefox Guide, e.g. Fast Back/Forward cache & error pages have been updated (As opposed to the standard error prompt).
One of (If not, the) final major feature that remains to be thoroughly tested is the improved Auto-Updater. Fancy testing it for Trunk builds?.
For Thunderbird fans be sure to check The Rumbling Edge.