Hi Apologies for the delay in getting to your question, but hopefully I can help. First off, thank you for giving Firefox Developer a try. I use it myself and really like it. Aside from the cool blue and black theme, and a heap of developer tools, it is a pre-release version so by using it and providing bugs, feedback and telemetry you are helping make Firefox better. There are several different ways to migrate across to Firefox Developer: 1) Use Firefox Sync to synchronize information between Firefox Release and Firefox Developer. This [https://support.mozilla.org/en-US/kb/how-do-i-set-up-firefox-sync article] will show you how to set up Sync and this [https://support.mozilla.org/en-US/kb/how-do-i-choose-what-types-information-sync-firefox article] will help you pick which information to synchronize. 2) Move Bookmarks manually by backing them up and reloading them ([https://support.mozilla.org/en-US/kb/restore-bookmarks-from-backup-or-move-them how to guide]), and moving passwords manually by copying across the key3.db and logins.json files from your existing profile. This [https://support.mozilla.org/en-US/kb/profiles-where-firefox-stores-user-data article] will show you how to find and open your profile. You may need to reinstall any Add-on. 3) Take a copy of your Firefox Release profile, find and open the profile folder in Developer edition and swap the file names round so that the "empty" Developer edition file contains the contents of the Release version profile, but with the developer edition file name. (Once the folders are open in Windows Explorer, you will need to close Firefox.) If I was running the two versions of Firefox in parallel, I would probably go for the first option, but if you are going to use Firefox Developer as your sole browser, the second option may be better. It captures bookmarks and the two files needed to run the password manager and moves them across. If you are going to be using either of the second two options, I strongly recommend copying files to another location so that should there be a problem you can reverse out without loss of data. I hope this helps answer your query, but if not please come back here and we can look into a different solution for you.

The Firefox Developer Edition can use the same profile as the Firefox release. The DE version uses a special "dev-edition-default" profile, but you can use the Profile Manager to create a new profile. *https://developer.mozilla.org/en-US/Firefox/Developer_Edition *https://developer.mozilla.org/en-US/Firefox/Developer_Edition/Reverting *http://kb.mozillazine.org/Profile_Manager *https://support.mozilla.org/kb/Managing+profiles ---- You can transfer files from a previously used profile to a new profile *https://support.mozilla.org/kb/Recovering+important+data+from+an+old+profile *http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox