I notice this behavior all times I move a sentence on a separate line: I delete a space character between two words with the backspace key, and the text cursor is moved to the next space; when I press Enter, the first word is left on the old line.
Is this a bug, a feature of Safari, or neither of them? (Therefore, it is a bug in third-party software)?
I noticed that something similar is still happening with OS X 10.8.3 and Safari 6.0.4: When I edit something I have written before, adding a space moves the caret to the end of the sentence I am editing. It doesn't happen all times, and I am not able to understand when it happens.
I don't have any utility that intercepts the pressed keys or the mouse clicks; the settings for symbol and text substitution and automatically correcting the spelling are disabled.