I am one of those who always experiments and tests with alpha or development versions of Firefox, I will honestly say that they tend to be as stable as the most, the problem is when I make changes in about: config
For example, I told you about a new feature that Firefox will incorporate in future versions (in v36 it should be ready), however I who use 32.0b4 already wanted to test it, see if it was functional, etc.
To do this I opened my Firefox, went to about: config and I edited a few lines, then I closed it and reopened it, that's when everything went wrong. Firefox would open me but it would get stuck, frozen, I couldn't interact with it at all, it wouldn't even let me go back to the settings panel to undo the change I had just made; and that it was obviously the one causing the malfunction.
Obviously I needed to undo what I just did, but… I couldn’t access anything in Firefox, that’s my problem
How to edit about: config without opening Firefox?
Fortunately, it is possible to make changes to the options shown in about: config Without even having to open Firefox, we only have to edit a file that is located in the folder that is our Firefox profile and that's it, the line to edit it in a terminal would be:
nano $HOME/.mozilla/firefox/*.default/prefs.js
This will open a file with a lot of options, which as I said before, are the ones we see in about: config, there we look for the line (or lines) that cause the error in the application and modify them, then we only have to save the file with Ctrl + O (or bear) and close it with Ctrl + X
Is it still not solved by deleting my Firefox profile?
Yes, you can simply delete the .mozilla folder from your home and the problem will be solved, but it is (in my opinion) too drastic a measure. It is as if to solve a simple problem in a file you formatted everything
If you delete your Firefox profile you will lose the history of accessed sites, saved passwords, add-ons or installed addons, everything. This is not something viable for me, it seems much simpler and more logical to simply edit a small file, repair the damage caused and that's it.
The end!
Well, nothing more to add, I hope it has been useful and… this reminds me not to play too much with Firefox's “hidden” options