We’re able to successfully use Cmd+F as expected on the home page in browser, but not on the desktop app. We’ll pass this onto our team - thanks again!
Our team confirmed that ⌘F was only designed to work inside of Figma Design and FigJam files, but not the file browser.
They appreciate this feature request though, since we could catch ⌘F and use that to trigger search behavior in the app. Stay tuned and keep an eye out for our future releases.