Why has the NoScript icon disappeared?

This happened because the Status Bar was disabled. Solution: use menu View/Status Bar to enable it.

"Firefox by default checks for plugin updates automatically, and then let you choose if you want to download and install them. As far as I can tell there is no automatic update without user interaction.

You can disable this check in the browser settings."

"I had the same issue--the NoScript icon had disappeared and wouldn't reinstall.

The solution was to uninstall ""McAfee SiteAdvisor"". Once I went to Control Panel → Programs → uninstall Mcafee Sitadvisor. Firefox restarted and NoScript was back."

"Firefox has a page called Add-ons that you access by going in the ""Tools"" Dropdown box. (On my MacBook it's at the top of the screen.)

By bringing up the Add-ons page - a listing of all Add-ons you've chosen - you will see the line with the NoScript Add-on listed. If you then hit ""MORE"", you >CAN choose to< select to STOP NoScript from continually updating itself, regularly, automatically on Firefox.

I probably wouldn't suggest doing that, as NoScript regularly adds fixes and updates to its scripts' response programming. But I wanted to let you know that it IS possible to select that (stopping the NoScript auto-updating) and not have to change the the overall auto-update status for Firefox, or your computer in general.

You're better off recreating/resurrecting the missing icon/button. I found MY missing NoScript Button on my Addon Bar, which I had UN-enabled (because I had had nothing on it & because the Status Bar seems to work better for me). By going (in Firefox) under the ""View"" Dropdown you can select ""Toolbars"" and then select/unselect 'Status Bar' and 'The Addon Bar'.

After I found my missing NoScript Button I went to the near-top /right of the Firefox Window/Screen and selected the Open Menu Tool - which is the =three=horizontal=lines=, one atop the other (looking like a FAT partial I-Ching Hexagram).

Once that box opens, at the bottom of the box you can select ""Customize"" - for Customizing Menu & Toolbars. After that's selected you can move around and rearrange icon items on various toolbars. I found my missing NoScript button on the now visible ""Status Bar"" (which I had just before re-enabled thru the ""View"" dropdown), and I MOVED it back to the Status Bar where it had previously been.

You can put the NoScript icon /button, or most anything else, almost ANYWHERE on these Firefox Window toolbars - where-ever you want them. But, be slightly advised that occasionally moving too many things around makes something seem to disappear again. I've had that happen and had to uninstall/delete the relevant Firefox Add-On, and then re-install it, just to get the missing button back. USUALLY, however, moving these little icon/buttons around isn't too much of any problem.

Good luck!"