Theme Font & Size Changer

Theme Font & Size Changer lets you change the global font size and font family used for the user interface in Firefox. Design your browser with your favorite font.
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Theme Font & Size Changer is a versatile browser extension that allows Firefox users to customize the font size and font family globally within the browser's user interface—including menus, toolbars, and windows. Unlike typical text zoom on web pages, this tool modifies the interface fonts themselves, making it especially useful for visually impaired users or those utilizing high-resolution or wide-screen displays.

The extension supports instant application of font and size changes across sessions, offering options to adjust zoom, font style, weight, color, and background color of toolbars and context menus. It includes a convenient toolbar button and a Tools menu option for easy access to settings. Additionally, it supports Thunderbird and SeaMonkey, providing a consistent customization experience across multiple Mozilla-based applications. With accessibility and personal design in mind, Theme Font & Size Changer empowers users to tailor their browsing environment to their preferences and needs.

Manifest V2
By:
Baris Derin
Daily users:
6,167+ 43
Rating:
2.22
(222)
Version:
62.1resigned1 Last updated: 2024-04-25
Version code:
5726050
Creation date:
2010-05-28
Risk:
High risk impact Moderate risk likelihood
Permissions:
  • tabs
  • storage
  • management
  • activeTab
  • downloads
  • contextMenus
  • <all_urls>
  • http://*/*
  • https://*/*
  • menus
    • See more
Size:
239.53K
Email:
su*****@barisderin.com
URLs:
Website
Full description:
See detailed description
Source:
Firefox Browser Add-ons
Updated:
a day ago

Ranking

# 1,027 ▼ 4
Other rankings
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User reviews

Multiple user reviews indicate that the Theme Font & Size Changer add-on does not work properly, especially with Firefox Quantum and newer versions. It lacks key functionalities like font resizing, and there is little to no ongoing development or updates. Installation is cumbersome, and users are advised that it may be discontinued. Overall, the add-on is considered non-functional and outdated.
Pros
  • None mentioned in multiple reviews
Cons
  • Does not work as intended
  • Not compatible with Firefox Quantum and later versions
  • No font resizing functionality
  • Lack of updates and maintenance
  • Users have to install it manually which is complicated
Recent reviews
by Endymion0000, 2025-04-10
by 远离中共邪教快退出党团队, 2025-04-01
by 退出党团队远离中共邪教, 2025-02-17
View all user reviews ›

Extension safety

Risk impact

Theme Font & Size Changer requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.

Risk impact analysis details
  • Critical Grants access to browser tabs, which can be used to track user browsing habits and history, presenting a privacy concern.
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  • High ******* ******* **** *** ****** ***** *** ***** ** ******* **** ********* ********* ** * *********** *****
  • Medium ******* ***** *********** ***** ****** ********* *** ***** ********* **** **** ************** *** ********
  • Medium ****** ********** ** ******** ********** *** ********* ******* ******** ****** ******** ****** ********
  • Low ******* ****** ** *** ********* ******** ********************
Risk likelihood

Theme Font & Size Changer is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

Risk likelihood analysis details
  • High This extension has low user count. Unpopular extensions may not be stable or safe.
  • Medium **** ********* *** *** **** *******
  • Low **** ********* *** ******* **** **** * ****** **** ***** ******** *** **** ****** ** ** ****** *** *****
  • Low **** ********* *** ***** **** **** * ****** **** ***** ********** *** **** ****** ** ** ****** *** *****
Upgrade to see full risk analysis details

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