Jeremy Corbyn dancing on the head of a pin

Jeremy Corbyn says he was "present but did not take part" in a wreath laying ceremony despite the existence of a photo showing him holding a wreath.

First question, at what point does one move from being merely "present" to "taking part"?

Second question, will the BBC ever cover this story with 1% of the forensic attention they've paid to Boris Johnson's burqua remarks? I think we know the answer to that.