This is a cute one.
Look at the highlighted text box in the attachment.
Take its length.
Did it come up 0 or did it come up 1?
I'll bet it came up 0.
The Blocks Editor has a nasty habit of trimming blanks from text blocks,
and an empty text block looks almost identical to
a text block with a space in it.
Make sure that space is really a space.
ABG