Last modified: 2013-06-18 00:54:42 UTC
If there are 2 blank lines (line breaks) then the paragraph immediately after is uneditable (green striped overlay). Confirm here: http://en.wikipedia.org/w/index.php?title=User:Quiddity/sandbox&oldid=560048320 and see thread here: http://en.wikipedia.org/wiki/Wikipedia:VisualEditor/Feedback#Paragraph_editing_disabled.3F.3F.3F
This (and similar issues if you have an HTML comment on a paragraph double-line before some content) is caused by bug 47403; I won't mark this as a duplicate of that one because we're still trying to get a comment as to what will break in VE if Parsoid reverts the hack that causes this.
This now works; you won't get blank lines causing the next line to be unable to be edited. Thanks for the bug report!