Tools Option: Choose Tools menu from Firefox Menu Bar and click on the Theme Font & Size Changer option.Toolbar Button: Click on the Theme Font & Size Changer button to open up Theme Font & Size Changer settings panel.There are two places that you can manage the global font size and font family of Firefox via Theme Font & Size Changer: While Theme Font & Size Changer was written to be used with Firefox default theme, it does work with other non-default themes, but you may come across issues where some elements within Firefox retain the (non-default) font size setting that the theme developer chose for their theme. It was initially created to be an accessibility aid for persons with visual impairments and for those without perfect eyesight, but it's also useful for Firefox users with high resolution settings and wide screens. You may assign your favorite font into your browser interface and change its size as you wish. All font size, font family, and other changes are applied instantly and they are saved permanently and through sessions. Different from add-ons that enlarge and reduce text on web pages, Theme Font & Size Changer changes the font size and font family in all windows, menus, toolbars, etc within Firefox itself. It is especially valuable tool for visually impaired people and wide screen users. Theme Font & Size Changer is a simple browser tool that lets you change the font size and font family of Firefox and several other Mozilla products.

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