change every web page style,darken background color and brighten text color,prevent users see high brightness web page.Firefox Addon edition:
https://addons.mozilla.org/zh-TW/firefox/addon/darker-bg-brighter-font/
If this addon have bad effect in particular page, go to that page and than click this addon button,set 'change colors function' option off, make 'change color function' do not use just in the domain of that page.
When loading web page, the quantity of wait-change-style elements displayed on this addon button.
This addon can setting options for all domain in "about:addons".
Click this addon button, user can setting options for specific domain of user browsing web page.
After changing the option setting, users need to refresh the web page, and than option setting will be applied to the page.
Some pages set color style with higher priority,results change color function of this addon be fail,enabling the option:"changing color has Highest Priority" will force change that color style,but may cause 'visited links color' and 'dynamic color changing effects' fail.
Some pages directly using high brightness background images,enabling the option:"Remove background images" can delete them,but also delete all background images in web page,if user knows how to edit css, recommend using stylish add-on and turn off "Remove background images" option, to obtain better results.
if using this addon and another addon:noScript at same time,and blocks script of web page, it may cause the change color function fail.
Reviews of Darker Background Brighter Font extension