Add-ons submitted to AMO (https://addons.mozilla.org) are being reviewed. So as long as you do install add-ons from AMO only you're reasonably safe. Be careful when installing add-ons from other sources.

So what you're saying is as long as I go to the mozilla site and get the add on from this specific site the add ons, etc are safe. If I go to a different website they may not be safe? I'm very leary of adding since I'm so new to all of this and did do an add on and got taken over. I ended up with a nasty virus or bug or whatever you want to call it and spent days getting it cleaned up. Thank you for your answer!

If I go to a different website they may not be safe?

What is your point? If you don't want to take chances, stick with AMO for installing add-ons, and don't install add-ons from unknown sources. It's as simple as that.

I'm not planning to go to any other sites but I got an add on that this site supports and got taken over by the bad virus. That is why I'm wondering if they are tested by Mozilla or Firefox. I know I didn't get the virus from any other place as I only had my browser open with that download. All of a sudden those obscure no name boxes were popping up. My virus scan was going crazy telling me I was infected. I lost a bunch of stuff and noticed stuff was added to my browser without my permission. I guess it's the chance you take when there are so many of these add on's and stuff. Anyway, thanks again!

What was the add-on you downloaded and from where?

By abine, do not track me. I don't know if it was a bad link or what but right after I added it everything went haywire.

By abine, do not track me.

I guess you couldn't be more specific than that?

https://addons.mozilla.org/en-US/firefox/addon/donottrackplus/

If this is what you downloaded, it certainly isn't a virus. I'm not using this add-on, and I have no intention to try it. But I think the add-on is legitimate. So my best guess is you did do something wrong. There are other add-ons to protect your privacy if this is what you're after. Take a look at AdblockPlus in connection with a privacy protection filter list. https://addons.mozilla.org/en-US/firefox/addon/adblock-plus/

Great! I'll try adblock plus. Thank you.

Sorry that you had a bad experience with a Firefox add-on, but it's not clear to me whether you downloaded DoNotTrackMe from here - https://addons.mozilla.org/en-US/firefox/addon/donottrackplus/ or whether you got it from the abine website - http://www.abine.com/donottrackme.html

That makes a big difference because the version of that add-on which is hosted at AMO is not the same as adbine is providing at their website. I saved both versions to disk and opened the XPI package of both to inspect the install.rdf file; while the overall XPI file size appears to be the same there are major differences in the install.rdf file - the abine version has its own Update URL listed, where the version at AMO would be updated thru AMO as almost all add-ons hosted at AMO are updated.

Minor difference? Or one that allows abine to do what it wants after installation?

Note that the word Add-ons does not only refer to Extensions but also Themes (both complete and light), Plugins, Dictionaries & Language Packs and Search Engines.

• https://addons.mozilla.org/en-US/faq
• https://addons.mozilla.org/en-US/developers/docs/policies/reviews

Thanks guys. I think I'm learning quite a bit. (I think) I'm not really sure what the difference is with add on's, plug ins, extensions and so on. I played around a little bit and wanted the google toolbar. It's not compatible with Firefox so I added the googlebar lite. It was there and now it's gone. I'm so old school. I would really like to go back to the old way of using a browser and toolbar and just be done with it all. The do not track was downloaded from abine. I supposed I could have contacted them to let them know but I was so angry and wasn't sure if I would end up getting hit with more by going back to their site. So, I'm learning and figuring out and hopefully will have it all the way I want. Off to find the googlebar lite....Have a good evening.

Oh and James, I bookmarked the links so I can refer back to them.