The index-finger salute to Trump reminds me of the "one way" gesture used by campus evangelists, where the one way is Jesus. If that's where it comes from, these people are equating Trump with Christ. https://www.washingtonexaminer.com/news/watch-trump-supporters-one-finger-salute-ohio-rally
Liberdon is a Mastodon instance for libertarians, ancaps, anarchists, voluntaryists, agorists, etc to sound off without fear of reprisal from jack or zuck. It was created in the wake of the Great Twitter Cullings of 2018, when a number of prominent libertarian accounts were suspended or banned.