Clarification requested for "open in dialog" functionality: How do we suppress the "close dialog" icon?

Question

I'm experimenting with turning certain Related Actions / Record Actions into the new(ly revived) pop-up dialog. To be clear, I love that this functionality is back and that it's now optional, in a pretty flexible manner, and especially that it's configurable per each individual use of the Record Action component. 
 My apparent issue: no matter what I have tried so far, the dialog will render with an "X" icon in the upper right corner of the form, which causes the dialog to instantly close without any confirmation. This seems to be the case regardless of whether the process is using a start form, or a regular User Input Task, either configured as a Quick Task or using the regular configuration. If there is a configuration that affects this, it has thus far eluded me. 
 Screenshot: 
 This opens up some particular, potentially severe issues. 
 
 In a "strictly sites" based configuration, which I'm currently working under, if a user has launched a process instance using a User Input Task, and they use the "close" icon to close out of the interface (regardless of whatever buttons the designer has provided), the process instance will then be orphaned in the background as the user has no particular way of navigating back to that task unless special measures have been taken to expose Tempo tasks to users of the site (which we have no plans to do, in our project at least). 
 If the user has entered some amount of data on the form (either a start form or a user input task), it can be fairly destructive if the form is allowed to be closed without confirmation, accidentally or otherwise. Yet the "X" icon causes the task/form to be closed, without saving, immediately, regardless of whether any amount of data has been entered. Designers should be able to force users to only be able to close a dialog via a "Cancel Button" click or similar, where we can conditionally require last-minute confirmation as to whether the user really wants to dump the contents of that form they just spent 10 minutes filling out. 
 Probably more that I'm not thinking of yet... 
 
 Can anyone from Appian confirm or comment on whether this behavior is intended? My expectation would be that there be some by-task and/or by-form configurability for this behavior, or at least that there be documented workarounds for ways to suppress it when needed.