Provide a multi-select custom field option within incident and service request forms -- ideally, a global field that spans any ticket type vs separate fields for incidents vs service requests. 

I searched the forums and found another person had asked for the same feature 2 years ago, but did not get much of a response other than "we'll add it to the feature enhancement list."  I received the same response to my inquiry.

If a multi-select option is not available, is there an option to place custom code within a form? 

For example, could I add a button that launches a popup that is hosted outside of ServiceDesk Plus, one that includes the ability to select multiple options, then save those options as text into a field on the form?

This kind of functionality and flexibility are options within other service desk platforms (Jira, Remedy, etc), so I hope this is coming soon to the platform, given its been requested by at least two people now.