When creating fillable fields, if I have previously created a field with multiline formatting, I often encounter a pop-up on subsequent fields if I attempt to create a date format, which tells me that I cannot format a multiline field as "date". In reality, I have not formatted said field as multiline, just a previous field.
In order to proceed with formatting my date field in this case, I have to enter formatting, and turn multiline ON, then OFF. Then I can go back to date formatting without issue. The same problem will occur multiple times per document if I have multiple date fields to format after creating a multiline field. I could do multiline last of course, but this involved a disruption to my usual work process.