Good evening Steve and welcome back!
Thank you for reaching out to us.
We are sorry to hear about the breaking words.
I would love to help you with this topic.
What is going on is that that specific WordPress theme has a CSS break-word rule for title tags.
Firefox just renders it accordingly (and differently than other browsers).
You might want to try the following CSS rule to fix that:
h3.tribe-events-month-event-title a {word-wrap: normal !important}
Let me know how that goes.
Best regards,
Geoff B.