I don't know about the release channel message. But there is a "bug" in Firefox 20 on Mac OS X where if you close all the pages and then Quit Firefox, it thinks it crashed and starts with the crash recovery screen on the next startup.

Two workarounds until this is fixed:

(1) Quit with at least one page open; or

(2) Don't try to restore the previous session after a crash. Here's how that is changed:

(i) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful.

(ii) In the search box in that tab, type or paste sessions and pause while the list is filtered

(iii) Double-click browser.sessionstore.resume_from_crash to toggle its value from true to false.

This should be fixed in a future release of Firefox.

Hello frelus, the "release update channel mode" is the channel will provide stable release versions, including security updates.

to fix your problem see jscher2000's reply.

just for information about firefox channel mode see: Update channels

thank you