We have an internally generated HTML email that creates links to a custom database. These links use a database called Filemaker and are of the format <A href=fmp://{link to database file and record>Some text</A>.

The emails are properly formatted and work fine from Outlook.

But the Zimbra web client breaks them. They are just completely removed from the email and don't appear as a link at all.

Is there any way to alter this behavior in the Zimbra web client?