- Block yourself, using a valid template in the "reason" field, e.g. {{blocked proxy}} on enwiki
- From the mobile interface, attempt to edit a page
A popup will show, saying "You have been blocked from editing".
The expected result is for the template to be transcluded in the popup, as it is in the desktop interface.
The actual result is just "Reason for the block: {{blocked proxy}}".
This is due to the limits of jqueryMsg, I'm guessing.