Add-on icons can't be found

Today I installed a new extension (Bitwarden) and want to add the icon to the toolbar. I can't find it anywhere. The add-on shows up in the add-on manager but there's nothing there to help me add the icon. The little puzzle piece in the upper right of the browser -- click on that and Bitwarden isn't listed.

How do I fix this? In Chrome there's a simple toggle switch in the extension manager to add the icon to the toolbar. Frankly, if I can't get this Bitwarden icon to display I can't use Firefox at all. Thanks.