Harry was lazily summoning objects to himself, and had created quite a mountain of items, when he realised there may have been a slight snag in his "tormenting Umbridge’ plan. Professor Flitwick was eyeing Umbridge curiously as he answered her questions. If there was someone in this school who would recognise a static jinx, Harry would put galleons on it being the charms Professor, who was still famous twenty years into the future as both a skilled Charms Master, and a duelling champion. Harry stopped mid spell to listen (the book he’d been summoning plummeted to the ground and nearly brained Lisa Turpin), and his heart sank when the Charm’s Professor’s eyes flashed with realisation, and he opened his mouth to speak. Thankfully, Umbridge herself managed to salvage the situation.