Steps to open multiple windows in Firefox:

• The Firefox icon can be found at the bottom of your computer screen. You can open a new window by right-clicking that icon. This will allow you to use two windows at the same time, each with several tabs.
• It's worth noting that if you hold down the Shift key while left-clicking a link, it will open in a new window. 
• Select Tools > Add-ons (or press Ctrl+Shift+A) from the menu bar, then the Extensions tab, and finally the Options button. Right-click the toolbar button in Chrome and select Options. There will be a new blue 'tiled-layout' button on the main toolbar after you install Tile Tabs WE.

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