These are some of the features of the Firefox browser, available for both Mac and PC.
As an alternative to having several browser windows open, Firefox allows you to open new pages as tabs in the same browser window. You can easily click on the top tabs to move back and forth between windows.

To open a new tab in your browser window, select New Tab from the File menu, or use the Ctrl + T keys (Cmd + T on the Mac). You can also right click (Ctrl + click if you have a one button mouse) on a link.and select Open Link in New Tab.
You can also set your browser to open links from other programs, such as email, in tabs instead of new browser windows. Set this choice on a PC from Tools > Options > Advanced > Select New Tabs Opened from Links. On the Mac, go to Firefox > Preferences > Advanced.
You can also bookmark a group of tabs if you want to open two or more at a time. Open the tabs you want to bookmark, go to Bookmark Page, type in a name for the group and check the box by Bookmark All Tabs in a Folder. To open the tabbed group, go to its folder in your bookmarks and select Open in Tabs.

To set or change your homepage, select Options from the Tools menu on the PC, or Preferences from the Firefox menu on the Mac. The General section has a section to type in an address for your home page, to set it to the current page, a blank page or a bookmark. You can also set your homepage to be a group of tabs that open when you start your browser; select the tab group from your bookmark menu.

You can change the size of the text on web pages, either for a particular page or for all pages. To make the text on a particular page bigger or smaller, go to Text Size on the View menu and select either Increase or Decrease. Select Normal if you want to return to regular text.

Permanent changes to fonts and colors can be made from the Tools > Options menu. In the General section, click on Fonts and Colors to set your browser preferences. You can set a minimum font if you want the text to be at least a certain size.
Go to Tools > Options > Web Features on the PC, or Firefox > Preferences > Web Features on the Mac, to block popup ads. Click the Allowed Sites button to add the URLs of sites where you want to allow popups.
Firefox can remember the passwords you use to log into websites. While this can save you time, it's not a good idea to use this on secure sites. Firefox does, however, allow you to set a master password to protect your passwords. To turn this feature on or off, go to Tools > Options > Privacy (Firefox > Preferences > Privacy on the Mac) then go to the Saved Passwords section. You can also view the sites for which you've saved passwords and delete the ones you don't want remembered.

Change the appearance of your browser by installing a theme, then selecting themes from the options menu.

Themes are found at:
https://addons.mozilla.org/themes/
Extensions are small programs that add features to your browser. Explore your choices at:
https://addons.mozilla.org/extensions/
Install the themes or extensions you want, then access them from the Tools menu.
If you're irritated by an animated .gif image on a web page, hit the Esc key. This will stop the animation.
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