This tests the ability to start editing in blocks that are visible, but have little or no content. Each of the divs below should be able to accept a caret.
This div contains some text.
This div is completely empty.
This div contains some collapsable whitespace (a '\n').
This div contains a self-closing p tag.
This div contains a self-closing p tag and some collapsable whitespace (two '\n's before and after the self closing p.