A heinous act by certain privileged individuals who believe that they have the right to not post on Twitter for a while. It's not as if you haven't been reasonable. You've called them a bitch, a troll, a racist, a transphobe and an utter disablist shitlord. Just to make it clear how keen you were to engage with them on the topic, you've even enlisted a few hundred of your closest friends to constantly send them tweets with the same message. But no, rather than stick around to listen to you telling them what an evil person they are, they've decided to log out and go and do something else! Like, gardening or going to work or something trivial like that.
Flouncing is an act that has a long history. For example, there's the Biblical Flounce out of Egypt.
This is when Moses and all his Twitter followers threw a strop over being called out by the Pharoah over his "Messenger of God" privilege, flouncing off to find their own social media network.
Then there's Napoleon's epic Flounce from Moscow.
A tantrum they had to throw over hundreds of miles, running the gauntlet of several hostile Tumblrs.
And of course, who could forget the Dunkirk flounce.
Thousands of British and French mansplainers, enduring constant bombardment by the Luftwaffe with Ally Cookies.