Unstraight or straightn't is an umbrella term for anyone that is not straight. It is similar to ultramoric.[1] Some may use this term rather than using 'queer', as some are uncomfortable with the word, due to its controversial history.
History
The first known use of unstraight was on February 8th of 2019, by Tumblr user beyond-mogai-pride-flags. Other uses appear over internauts, such as straign't, and strain't.
Flag
The flag was coined by Tumblr user beyond-mogai-pride-flags on February 8th, 2019. It has no confirmed meaning.