PUBLIC MARKS from decembre with tags url & userstyles

Users can currently install from other sources in these ways: Visit a CSS file, click the Stylish icon, click Add File to Stylish (no metadata will be loaded, but updates will work) From the Stylish tab in the Add-ons Manager, click Install from URL, and provide the URL to a CSS file (again, no metadata, but updates work) Modify the setting extensions.stylish.install.allowedDomains in about:config and visit a site that implements the appropriate meta elements and something like this JavaScript and use its UI (supports metadata). Use Install from URL and provide a URL that implements the appropriate meta elements. This way, the site does not need to implement any JS and does not need to be in extensions.stylish.install.allowedDomains (supports metadata) So basically the missing portion to achieve what you want is some way to more easily add a site to extensions.stylish.install.allowedDomains. I would also to give some thought as to how to prevent abuse of this feature. For example, there's nothing currently stopping a site from opening infinite prompts until the user installs.