What it does: it cuts brightness level by 2/3 so your eyes won't bleed if your game got bugged with excessive brightness after fallout 1.8+ update.
How to install: activate the plugin, load the game, open the game console, type "help brfix 4" to find the exact imad entry, then type "imod xx000f80" (replace xx with the number you've got in the previous step). effect will persist through the saves.
Uninstallation: use "rimod" instead of "imod", then save the game. do that BEFORE disabling the plugin or you're screwed. probably.
Bugs: made by bethesda.
Compatibility: everything.
Made with: fo4edit 3.2