The recommended way to install user styles is to use Firefox with Stylish.
If you already have Firefox with Stylish, make sure this site is allowed to run JavaScript.
You've installed this user style in Stylish. To uninstall it, open the Tools menu, choose Add-ons, click the User Styles panel on the top, click on the entry for this user style, and click Uninstall.
You've installed this user style in Stylish. To uninstall it, open the Tools menu, choose Stylish, and remove the entry from there.
You've installed this user style in Stylish. To uninstall it, click the wrench icon, Extensions, click Options beside the entry for Stylish, and click delete for the appropriate entry.
You've installed this user style in Stylish, but a newer version is available.
To uninstall this user style, open the Tools menu, choose Add-ons, click the User Styles panel on the top, click on the entry for this user style, and click Uninstall.
The recommended way to install this user style is to .
Warns you if a link is to a pdf, exe, mailto, or anything not that isn't a web page. It does this by placing an icon after the link. See the picture for more details. You can personalize it to your own needs by adding or removing your own file types.
This style uses icons from Windows. Linux users, check out Link Warning Mod (Linux compatible). Mac users, do you guys even use Firefox? This system isn't foolproof because it merely checks the end of the url. Also, this style works in Gecko only.