Hello,
We discovered an unfortunate little bug with 1.17 (stable) that has me perplexed. One of our processes is any items that need to be faxed, we use faxlogic.com, which is an electronic fax provider. To create a fax, we simply set up an email XXX-XXX-XXXX@companyname.faxlogic.com where XXX... are the fax number.
It's a quite simple user friendly process, it just converts the email to a fax and/or PDF where appropriate. We've used osTicket for going on at 7 years sending out faxes (and creating tickets for them in the process). However, we've been getting calls from recipients since implementing 1.17 over the weekend and returned faxes showing a completely incoherent fax with the same tell-tale message every time (circled in green in the image below):

NOTE: if you need a copy of the correct format of the fax for comparison, I will need to send it to you privately as it does contain PII.
We have been able to work around this issue because I discovered that anything that is resent or sent after ticket creation sends normally. So it is only when you click "New Ticket" and enter a response into those first fields, that it throws this strange formatting error into it, so my assumption is it's something on that page.
I have tried reverting these changes:

thinking it might possibly have something to do with it, but it makes no difference. I'm nowhere near a php Jedi, so I'm lost as to where to search after that. 😅
I contacted FaxLogic support and they are interested in knowing what is causing this (I'm thinking they may want to update on their end, but that's just speculation).
Any ideas are appreciated!