Hi, one common reason for this in recent months is users switching Firefox to using Automatic private browsing ("Never Remember History") without setting all their extensions to run in private windows. To check on that:

You can manage extensions on the Add-ons page. Either:

• Ctrl+Shift+a (Mac: Command+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons
• type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions. On the right side, find the "Manage Your Extensions" heading.

Each extension title can have zero or more icons next to it. The one indicating that the extension is allowed to run in private windows is a purple circle with a white mask:

If there are extensions that you want to run in private windows that don't have the mask icon, click the title and scroll the Details panel down to where you can adjust the permission:

Does that help or are the extensions still not functioning?

thanks for the help! All of them now work perfectly except for one which i allowed run in private windows(also got the incognito icon besides it) but still hasn't shown up on the toolbar.

i tried restarting firefox but to no avail...

Sometimes buttons get lost. You can check the overflow menu (>> icon) and the available buttons box on the Customize tab: Customize Firefox controls, buttons and toolbars. Any luck?

yep it's in the customize tab. thanks!