Show side and top bar not working on all monitors

I have trouble with my gnome extension for multi monitoring. I whant to show the top bar also on the second monitor, but the extension does not work. Also the warning symbol appears always also after reinstalling.

The slider is grey and can not moved.

Do you have tips or ideas how to fix that?

I found the solution:

• Open Firefox browser to manually add Gnome-shell extensions as add-on in firefox

• search in the GNOME library of firefox addon "Multi Monitors Add-ON"

• in the side select "update manually" now in the picture there is just an "ON" slide switch

• accept the updating process

• enjoy all multi monitor features

:-)