A simple FireFox add-on that inverts the web page colors (including images) to make pages easier to read in darker settings.
Github repo: https://github.com/Max-Github/FireFoxInvertColors

Invert Colors - A Firefox Add-On for Inverting Webpage Colours
"Invert Colors" is a user-friendly Firefox add-on that helps enhance user experience by inverting the colors on a webpage, making it easier to read in darker environments. The add-on features a toggle button and hotkeys for both global (alt+shift+r) and tab-specific (alt+r) color inversion. Note: This extension is currently not compatible with Firefox on Android.
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Not available on Chrome
Not available on Android
Not available on Edge
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Add-on summary
A very basic add-on that inverts the colors of the website. Includes a Toggle Button.
Colors can also be inverted globally using the hotkey (alt+shift+r). Or only on the active tab using (alt+r).
Note that currently this extension does not work with Firefox on Android, as the "browser.tabs.insertCSS" api just does not work work on Firefox on Android.
User reviews
Pros
- Helps reduce eye strain and provides comfort for reading large texts.
- Has an option to keep images in their original colors.
- Works well on most pages and is especially helpful for users with vision issues.
Cons
- Doesn't work on certain websites, including addons.mozilla.org.
- Images may still get inverted even with settings applied.
- The toolbar button changes all sites, which can be annoying for those with optimized dark modes on particular sites.
Most mentioned
- Eye strain relief
- Issues with functionality on certain websites
- Inversion of images despite settings
User reviews
by 远离中共邪教快退出党团队, 2025-02-12
Самое лучшее расширение для отображения символов на черном фоне. Комфортно просматриваются большие тексты. Глаза меньше устают.
При этом в настройках можно быбрать
параметр -> (Изображение, графику не инвертировать). То есть изображение и графика просматривается в обычном виде.
Из всего опробованного, это расширение лучшее. Рекомендую.
by Андрей, 2024-11-21
It works well. A big advantage of this addon is that it has an option to keep images in their original colours.
by Dragos, 2024-11-14
Add-on safety
Risk impact
Invert Colors 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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Risk likelihood
We don't have sufficient data to confidently determine the risk likelihood of Invert Colors. Use it at your own risk.
Risk likelihood analysis details
- High This extension has low user count. Unpopular extensions may not be stable or safe.
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