We're starting to deploy Redmine when a user pointed out that the address provided needed to be updated and should be a hyperlink. I created a normal a tag with an href that goes out in the text/plain section of the email but not the text/html section of the email (which is what Thunderbird displays). Is there some conversion / editing going on here?

Example:
To: undisclosed-recipients:;

----==_mimepart_547f7f622b402_2fb94315160474c9
Content-Type: text/plain;
charset=UTF-8
Content-Transfer-Encoding: 7bit

This is a test email sent by Redmine.
Redmine URL: https://---.---.com/---/redmine/

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----==_mimepart_547f7f622b402_2fb94315160474c9
Content-Type: text/html;
charset=UTF-8
Content-Transfer-Encoding: 7bit

This is a test email sent by Redmine.
Redmine URL: https://---.---.com/---/redmine/

----==_mimepart_547f7f622b402_2fb94315160474c9--

And here's our information page:

Redmine 2.5.2.stable
Default administrator account changed True
Attachments directory writable True
Plugin assets directory writable True
RMagick available (optional) True
ImageMagick convert available (optional) True

Environment:
Redmine version 2.5.2.stable
Ruby version 1.9.3-p547 (2014-05-14) [x86_64-linux]
Rails version 3.2.19
Environment production
Database adapter Mysql2
SCM:
Subversion 1.6.11
Mercurial 2.4
Git 1.7.1
Filesystem

Redmine plugins:
readme_at_repositories 0.2.1
redmine_agile 1.3.3
redmine_backlogs v1.0.6
redmine_contacts 3.3.0
redmine_contacts_helpdesk 2.2.12
redmine_ldap_sync 2.0.3