Was it for a plugin? You can manually adjust plugin permissions using the Permissions panel of the Page Info dialog.

You can call that up using any of these:

• right-click a blank area of the page and choose View Page Info > Permissions
• (menu bar) Tools menu > Page Info > Permissions
• click the padlock or globe icon to the left of the site address, then the ">" icon, then More Information > Permissions

Near the top, you'll find a list of plugins with individual permissions. If any of them is modified from the default, try clicking the Use default radio button to restore the default permission.

Does that work?

Did you try to click a possible Lego block icon at the left end of the location/address bar of click the Site Identity Button?

The "Site Identity Button" (globe/padlock) at the left end of the location/address bar drop-down shows what exceptions you have made on a specific web page.

You can consider to clear the Site Preferences or possibly use "Forget About This Site" to only remove data from one domain.

• clearing "Site Preferences" clears exceptions for cookies, images, pop-up windows, and software installation and exception for password and other website specific data

You can remove all data stored in Firefox from a specific domain via "Forget About This Site" in the right-click context menu of an history entry ("History > Show All History" or "View > Sidebar > History") or via the about:permissions page.

Using "Forget About This Site" will remove all data stored in Firefox from that domain like bookmarks, history, cookies, passwords, cache, and exceptions, so be cautious. If you have a password or other data from that domain that you do not want to lose then make sure to backup this data or make a note.

You can't recover from this 'forget' unless you have a backup of the involved files.

If you revisit a 'forgotten' website then data from that website will be saved once again.

Thank you jscher2000. Your solution worked perfectly.