Tab Scope is an add-on that does this for you with ease. Just install it and you’ll get lightweight previews for your tabs.
Install the Tab Scope add-on for Firefox; you will need to restart your browser.
The add-on works right out of the box, so you’ll immediately be able to preview your Firefox tabs just by hovering your move over them. You can also customize the addon within its Preferences.
Press “Shift + Ctrl + A” (or “Shift+ Cmd + A” for Mac) to open up the Addons Manager, and click on Preferences next to Tab Scope to open options. You can change things such as the appearance and alignment of the preview popup, the wait time to show popup, the width and height of the popup, zoom ratio and more. Click close when you’re done to see your new changes.
