The Firefox button has already proved to be what the Brits would call a Marmite moment – you either love it or hate it. If you hate it with a passion, get rid with the App Button Remove Add-on. But if you love it, you may find it’s awkwardly placed: it disappears when in full-screen mode, for example, or when the menu bar is enabled.
The Moveable Firefox Button Add-on fixes this by transforming the Firefox button into an App tab. This can then be dragged into an alternative position by right-clicking it (or any other element) and choosing Customize to open the Customize Toolbar dialog box. Placing it in on the Tab bar ensures it’s always visible too. And if you decide it’s not for you, disable or remove the add-on to return things to normal.
If you find the Add-on useful, the author requests a donation of $1.35 to help fund future development.