Add icon to Universal Toolbar for "Link Hotspot"

I want to add a Toolbar button to the mail template’s Universal Toolbar for Create/Hotspot/Link Hotspot. When customizing the Toolbar, there are other options for Hotspot buttons, rectangles, etc., but not the basic Link Hotspot.

Creating hyperlinks to filepaths should be so much easier than having to go through the menus and several steps.

Thanks in advance.

Wendy

Subject: Add icon to Universal Toolbar for “Link Hotspot”

Has anyone done this or know how one would go about doing it?