While this isn’t strictly the Facebook app for Roku, the result is the same.
you’ve got the option to browse your profile or watch Facebook Live orFacebook Watchon your television.
ensure your Roku equipment is correctly connected to your TV.

Then verify your Roku is on the home screen.
Using the Roku remote, scroll down and selectSettingsat the bottom of the left-hand navigation menu.
SelectScreen Mirroringand choosePrompt,Always allow, orNever allow.
In this case, eitherPromptorAlways allowwill work.
Give your Roku a few minutes to search for your mobile gear.
Once you see it on theAllowed devicesmenu on the right side of the screen, opt for unit.
Launch the Facebook app on your mobile unit, and it should display on your TV.