The 35-year-old actress flaunted rainbow-colored fingernails in two selfies and a close-up of her manicure, writing, "Putting the B in #LGBTQIA for over two decades" in the caption.
Commenters hailed Fox as a bi "queen and icon." One wrote, "You made us realize the B in a lot of us," while another joked, "My boyfriend and I aren’t even that serious."
As Yahoo! notes, Fox first publicly spoke about her sexual orientation in a 2008 GQ interview, revealing her crushes on Olivia Wilde, porn legend Jenna Jameson and a brief relationship with a female exotic dancer.
"I'm not a lesbian. I just think that all humans are born with the ability to be attracted to both sexes. I mean, I could see myself in a relationship with a girl."
"I think people are born bisexual and they make subconscious choices based on the pressures of society," she shared, adding that she is a "hypocrite" because she wouldn't date a bisexual woman," she said.
"That means they also sleep with men, and men are so dirty that I'd never want to sleep with a girl who had slept with a man," she added.
Fox's Pride tribute comes days before the limited theatrical release of Till Death on July 2. The horror flick stars Fox as a woman who's literally left "handcuffed to her dead husband as as part of a sickening revenge plot," Bloody Disgusting reports.
Check out the trailer above.