The problem was that publishing a card with `#publish` was tracking the event
after updating the status, which was clearing the saved changes and preventing the
code from detecting the mention.
See:
https://app.fizzy.do/5986089/cards/2835
This wasn't working when creation and publishing happened on separated instances
of the same record, which is what happens when you edit a draft and then you
publish it
https://app.fizzy.do/5986089/cards/2835/edit