LOS ANGELES — When Time magazine put actress Laverne Cox on its cover last year and proclaimed transgender rights as “America’s next civil rights frontier,” activists sensed their fight was moving in the direction of acceptance.

The video game “Dragon Age: Inquisition” soon introduced a transgender character, Amazon’s online TV show “Transparent” picked up a Golden Globe for its take on a transitioning retired professor, and even “South Park” won praise for an episode on gender identity.

And then Bruce Jenner happened.

For months, the 65-year-old former Olympian has been the subject of open speculation that he was transgender. Tabloids pointed to his longer hair and painted nails, paparazzi zoomed in on his every move, and a celebrity magazine manipulated an image of Jenner to look like a woman.