There might be add-on that has that specific design.

Among Firefox's built-in features, you might consider having the Permissions Manager open in a tab for easy access instead of having to open the cookie exceptions dialog each time. Here's how:

Type or paste about:permissions into the address bar and press Enter to open it. (Feel free to bookmark this page.)

On the left side, Firefox will list all sites with history, cookies, site-specific permissions, etc. If there is a site you know you want to manage permissions for, you can type part of the address in the search box above the left column to filter the list. If you click any site, you can see the current cookie count and adjust the cookie permission on the right side.

Hi, you could also have a look at the Permissions tab in Firefox Page Info window.