The Brief: Ok Trumper is a dismissive response similar to Ok Boomer that's meant to be directed specifically towards Trump supporters.

DEEP DIVE
From the get-go, Ok Boomer has had a political leaning. The phrase is an effective Millenial and Gen Z response to being called a snowflake. To be called a boomer often has more to do with one’s politics than it does with one’s age. “Ok Trumper” is an updated version with a more explicitly political angle.
The hashtag #OkBoomer started trending on Twitter after Republican political strategist Rick Wilson used it in a response to a Tweet by President Trump. Wilson, who is on the cusp of the Baby Boomer generation and Gen X, responded to @realDonaldTrump’s November 16 tweet quoting Rush Limbaugh with “LOL OK, Trumper.”
Do I detect a hashtag? #OKTrumper
— G Dan (Not Moscow) Mitchell (@gdanmitchell) November 16, 2019
The hashtag and phrase have since been used just as “Ok Boomer” was, but more specifically as an insult directed towards Trump supporters.
As Thanksgiving is coming up, some Twitter users have suggested that “Ok Trumper” will be a useful response for political conversations with Trump-supporting relatives at Thanksgiving dinner.
Talking to your uncle At Thanksgiving dinner #oktrumper pic.twitter.com/AyxI8oKGbP
— Moe (@MauriceHayes86) November 18, 2019
Gotta say #oktrumper is going to be pretty useful and cathartic at holiday gatherings. pic.twitter.com/5taF3SiaKa
— Intellectual Duck Web πΊ (@pixelkitties) November 18, 2019
This is the realist tweet out there at the moment. #oktrumper ππΌ pic.twitter.com/epcso2WCTb
— π‘π¦πππππ£π¦ππ (@pucknfruck1) November 18, 2019
Me watching #oktrumper starting to trend pic.twitter.com/pE5wDyvRw6
— Natalina (Ξ¦ αΊ Ξ¦) FUCKING (ΰΉβαΊβΰΉ) Wine-Mixer (@NatalinaWineMix) November 18, 2019
#oktrumper is legit the baddest mf hashtag of the decade. π€£
— Shocktimus (@shocktimus) November 18, 2019
Here, made something for you all to use in your replies:#oktrumper pic.twitter.com/AQ863BEziP
— NG (@sendmethecats) November 18, 2019
#oktrumper might be the best hashtag ever created. Start practicing your delivery for Thanksgiving when you have to deal with your aunt and uncle from Wyoming now. (see below.) ππ» pic.twitter.com/Ob8xUsUArU
— Amee Vanderpool (@girlsreallyrule) November 18, 2019