Extraneous nl2br in Activity details

[mlutfy]

How to reproduce on http://dcase.demo.civicrm.org :

• Go to a contact record
• Create an activity
• In the details field, add 3 separate lines (by hitting 'enter' once, to create a new paragraph).

Result:

In the above, you can see that "Line 1" and "Line 2" have a lot of space between them. Inspecting the HTML, it shows that some extra 'br' tags were added between the paragraphs.

If we edit the activity again, the HTML looks OK:

(the newlines in the above screenshot are what made me assume this is a nl2br bug)

[mlutfy]

I think this might be caused by: https://lab.civicrm.org/dev/core/issues/2

[mlutfy]

Closing in favour of: https://lab.civicrm.org/dev/core/issues/379