I claimed a dream disney channel introduces first openly trans character
You're likely referring to the Disney Channel show "Andi Mack" which introduced a main character, Cyrus Goodman, who is openly transgender. Cyrus, played by actor Joshua Rush, is a close friend of the main character Andi and is a part of the show's main cast.
Cyrus's storyline on the show explores his journey of self-discovery and coming out as transgender. The show's creators worked closely with the LGBTQ+ community and transgender advocates to ensure that Cyrus's storyline was handled respectfully and accurately.
"Andi Mack" premiered in 2017 and ran for three seasons, concluding in 2019. The show was praised for its representation of the LGBTQ+ community, particularly in its portrayal of a transgender character in a positive and authentic way.
It's worth noting that "Andi Mack" was not the first Disney Channel show to feature a transgender character, but it was the first to feature a transgender character as a main cast member. The show's representation of Cyrus and his story helped to increase visibility and understanding of the transgender community, particularly among young audiences.