X is still the dominant social media platform, but its daily active user base has declined and competitor Threads is seeing higher rates of growth.

Linda Yaccarino, whom Elon Musk hired to run X in 2023, grappled with the challenges the company faced after Mr. Musk took over.

Happy Thursday! I’m Andrea Jiménez, the tech bureau’s news aide, announcing some changes to the Tech Brief. The Thursday edition will highlight a selected Post story and continue the comprehensive tech policy news roundup that we have always run in every brief. The Tech Brief’s Tuesday edition will stay unchanged and be anchored by Will Oremus.

The CEO of X, Linda Yaccarino, said on Wednesday she would step down from the role in a surprise move, ending her tenure at the Elon Musk-owned social media platform that has faced several controversies and challenges including a mass exodus of advertisers from the site.

Musk tapped Yaccarino to replace him as CEO in 2023, shortly after purchasing the platform, then called Twitter, for $44 billion in October 2022. He said Yaccarino would focus primarily on Twitter's business while he focused on product design and new technology.