Enter about:config in the address bar and confirm that screenshots.browser.component.enabled = true.

Thanks for your quick answer. It's already true, but this missing icon (screenshots) does not appear (see attached screenshot)

OK. What about extensions.screenshots.disabled? It should be false.

extensions.screenshots.disabled was true

I will change and try again, sorry for my delay

regards otmar

That was the solution, although I had to restart firefox after changing

extensions.screenshots.disabled

Thanks a lot !

Best regards, otmar