Currently, I don't see a way to do that. On desktop versions of Firefox, if you type an asterisk into the address bar and then a space, your results will be restricted to bookmarks. That doesn't work on Firefox for iOS. And since the asterisk is on a third level keyboard, that probably wouldn't be the most convenient way to implement it anyway. Do you have an idea about how to make it usable? Mozilla has set up a special page for feature suggestions for Firefox for iOS: https://fxos-ios-browser.ideas.aha.io/ideas/new Or you also could use the more general feedback page accessible through the Settings dialog: * Tap the tabs button * Tap the gear/wheel/cog icon * Tap "Send Feedback" to open the feedback page