Missing date picker for expiration date in Firefox

Install Nuxeo 9.2 and WebUI

With Chrome (see chromeDatePickerIsPresent.png)

1. create a File document
2. set an expiration date
3. save the document
4. double-check the expiration date is present by exporting the document as XML

With Firefox (see firefoxMissingDatePicker.png)

1. create a File document
2. set an expiration date -> not possible
3. observe the triangle for opening the date picker does not appear