ubuntu+Yota+ Firefox offline

toolkit.networkmanager.disable to true?

Offline because NM thinks the connection is missing when in fact it is. Try the following solution. It works, although the on/off of the connection you have to use the "button". Well, or to cut NM in General, if it is not needed :)

I also recommend to install the extension "Work Offline" in Firefox in order to have on hand (in the status line) indicator of autonomy of the regime, and not in the menu to climb. This will save a lot of time when checking the above recipes.