Hello there,
we are on version 1.18.11 and noticed the following behavior:
When the user has the settings "Editor spacing" set to" Single line", the text entered (whether is by typing or pasting) does not get wrapped in <p> elements. Hitting Enter will properly generate <br> elements to honor the single line preference, but the text does not get enclosed in a paragraph element.
This leads to error 403 (Forbidden) when you hit "Post reply"
If the settings is "Double line" then all works fine.