I've got a black line in my Firefox address bar
 

It seems like it happened when I upgraded to 14.04. When I first open Firefox the line isn't there, but as soon as I enter something and the site comes up, there is a solid black line over the address bar. (see screenshot) When I put the cursor on the right end of the black line and hit the left arrow (not the backspace), the line (space by space) disappears. Any ideas? Thanks!

Hi Gregg,

Try to close Firefox and remove your firefox settings.


To prevent any lost just rename your folder ~/.mozilla to ~/.mozilla.bak (Firefox closed)
Restart firefox after that.

what happens when you type an address and then highlight it?

Thanks, angel, but your advice was a little beyond my skill level. I wasn't sure which folder you were telling me to rename, and what the command you suggested would do, and if it was two steps I was supposed to do or just one. (At this newbie stage I need real specific step by step instructions.) Thanks.

Nothing. The address just stays highlighted.

Regarding Angel's suggestion about the .mozilla folder, here's more info.
Any file or folder beginning with a full stop "." is called "hidden". This means that .mozilla in your home folder (/home/Gregg/ or whatever you username is) will not be seen unless you take special measures. For example if you're in your home folder and from a terminal you issue the command:
you'll see a lot of files & folders but not any hidden ones so not .mozilla. If you enter the command
you will see all your files & folders of your home directory including the hidden ones.
To change the name of any file or folder from a terminal you use the mv (meaning "move) so in linux-speak changing the name of a folder/file from A to B is moving the file from A to B. Get it?
So Angel gave you the command to do just that. His command means that you are renaming (moving) the .mozilla folder of your home directory from .mozilla to .mozilla.bak
You could change the name to aardvark but Angel's suggestion has the benefit of not taxing your memory if you want to move .mozilla.bak folder back to its original name.
Hope that's clear enough.
jdk

so the highlight is not black on black, and your issue is definitely not related to gui styling/theming? tried different themes? logging out/in?

LZM jdk, Thanks for the amplification. I did indeed change .mozilla to .mozilla.bak but when I opened Mozilla (it asked if I wanted to import Chrome favorites and cookies and I said yes) the black line was still there.

And the mv thing is cool for renaming stuff, but why did .mozilla come back after I had "moved" it to .mozilla.bak ? (see screenshot)

Thanks ondoho. When I log out and then go to log back in I get this (see screenshot) and I can't log back in.

And no, the highlight is not black on black--it disappears with the arrow keys.

I haven't done any switching of the themes or styles so I don't think that's it. (I just have a dark blue background for the desktop.)

It came back because Firefox always checks if you have that configuration file in your home directory. If you don't have it, it will create it and use it to store your personal stuff such as configuration settings, bookmarks, plugins, etc. Deleting the file as Angel suggested is a way of getting Firefox back to its "factory settings" and a eliminate any of your personal settings as a source of your problem. If your problem persists (and it does) then you can delete the new .mozilla file and rename .mozilla.bak to .mozilla and things will return to the way they were.
jdk

Must be a firefox thing, if it happens only in firefox.
have you searched their help database?
weird that it only appears in the url bar.
unless you get a handle on the problem there's no way to grasp it.
some kind of logic on when it happens and when not.
have you tried changing themes, just for troubleshooting? both firefox themes (complete themes, not just personas) and GUI themes (GTK i guess, whatever unity is using).

Thanks jdk LZM extraordinaire (I have to give you a superlative title if I'm a LZM) for explaining the mysterious reappearing .mozilla folder. Thanks to your encyclopedic knowledge I have banished the upstart .mozilla.bak and restored the rightful .mozilla to its deserved eminence. (This stuff is good to know though. Getting comfortable with doing stuff in the terminal. Thanks.)

Thanks ondoho. I went to firefox help. Nothing in the data base. (Seems I am singularly blessed to have this problem.) Googled it and got this LOL (see screenshot). I don't think it's the themes because (speaking of a kind of logic) it happened to both my Xubuntu computers simaltaneously, and the only variable those computers have gone through together is the upgrade from 13.10 to 14.04.

You know, I really think it's some sort of security feature from the NSA. Because the address bar is fine and I can enter the address, but as soon as the computer goes to that address the address is blacked out, as if the computer (or NSA) doesn't want me seeing the address I've just typed in. Which I realize makes no sense now but when I first thought of it it seemed plausible.

Unless the solution descends from the stratosphere and lands in my lap, I think I'm going to bail on this. The computer functions. It's a minor inconvenience. And, who knows, some people might wish for such a cool feature. :)

is your system working perfectly (or at least normally) after the upgrade?
there is absolutely NO other issues that might be related?
are you using any weird ff add-ons?

i just tried 4 differently phrased web searches and got nothing, either.

have you opened a topic on ubuntuforums? you should.

btw, i think upgrades from one distro number to another (like, 13.xx to 14.xx) are discouraged? not sure though.

Try: