Steps to reproduce:

• In Moodle core, set the defaulthomepage setting to "Home"
• In Boost Union, enable an advert tile on the frontpage and / or add a block to the "Content (upper)" region on the frontpage
• Go to the site support form on /user/contactsitesupport.php
• Send a test message
• Verify that you get redirected to the frontpage

Expected result:

• The success message is shown at the top of the frontpage

Actual result:

• The sucess message is shown above the main frontpage content, but below the advert tiles / content block