Currently, Datetime field types in general (including lead fields and not just custom objects) are limited to be filtered in a smart list by date and not including time.
We use a custom object for our webinar (through a webinar provider). Within the custom object there is a field called "Registration Date". It has a "type" as "datetime" When I view an object I can see the time stamp. However when I run a smart list based on the webinar object fields, I am unable to use the "time".
Our use case is that we want to capture true no-shows for a webinar so we need to be able to filter people from the time the registration date within the object. So if the webinar started at 9:00am on 4/15, we would do a Smart list filter to say give me all leads who registered before 9:00am on 4/15/19 and have no views of the webinar. Those are the true no-shows.
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