If there is ever a reboot, it will be without the creator Joss Whedon.

... Excerpt from Firefly: Will Disney+ Revive The Series?:

Joss Whedon Will Not Be Involved

Since Firefly was his vision, many wondered whether Joss Whedon would return for the reboot. While Whedon isn't a stranger to creating television properties — Buffy the Vampire Slayer is beloved to this day — the allegations of workplace harassment might be why he won't be returning. WarnerMedia conducted an investigation, resulting in swift action from the studio. Whedon then exited the HBO Max series The Nevers, and it’s safe to assume that producers, especially Disney, are cautious about working with him. He has not directed any television shows or movies since leaving The Nevers.

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