What happens when you try to use the screenshot feature?

Users occasionally report that the right-click context menu item for "Take Screenshot" suddenly disappears, and/or the keyboard shortcut Command+Shift+S stops working. In that case, please check this setting:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

More info on about:config: Configuration Editor for Firefox. The moderators would like us to remind you that changes made through this back door aren't fully supported and aren't guaranteed to continue working in the future. Since this is restoring the default setting, I feel comfortable mentioning it.

(2) In the search box in the page, type or paste extensions.screenshots.disabled and pause while the list is filtered

(3) If the preference is bolded and has a value of true -- true meaning it is disabled -- double-click it to restore the default value of false

If that preference was locked (unchangeable), type or paste about:policies in the address bar and press Enter/Return to load that page.

Normally, the "Active" panel just says this:

The Enterprise Policies service is inactive.

If yours mentions "DisableFirefoxScreenshots" that could be causing the problem. Is this a managed computer, i.e., an IT department could be modifying your software?

Let us know if any of the above has helped so far.

Well. I just restarted Firefox, and ... Bob's yer uncle! It works fine. Thanks anyway.