They are doing what they usually do when they lose the White House... trying to de-legitimize the new Republican president. It's an Alinsky tactic.
You're right about Libtards and the Constitution... they only care about it whenever they can cling to it in the occasional fit of virtue signaling. If they can exploit it to support their argument, they will parade it around proudly. Otherwise, it's just a dusty old relic written by bunch of racist slaveholders. Same with Patriotism.
"Anyone who doesn't respect the peaceful transition of power is a threat to our democracy!" ~Hillary Clinton, October 2016