Malware alert! Rated 1 out of 5 stars
This add-on contains malware. If you've customised your FX29, it's going to mess up your firefox button, your reload button, your stop button, and basically the entire chrome of your browser. Don't tell me I didn't warn you. Malware stays even after addon disabling. I'm still struggling to fix my browser and make it how it used to be. The idiot who made this add-on should be blocked from making any more.
Edit: Ok, fixed the firefox button but my reload and stop buttons still take up nearly half the space on my screen. Terribly annoying.
No, not malware
Shame you didn't bother asking me for help; I'm usually happy to help with any problems or feature requests, but maybe not so much after I've been called a malware writer on a public forum.
I can't think of anything URL Link does that could possibly have any of the effects you describe here, and I also can't conceive of a way in which those effects might persist after you uninstall an extension.
URL Link does not contain, and has never contained, any form of malware, and has lots of satisfied users. Unpack the XPI (a ZIP file) and check the code for yourself.