You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser.
macrumors 68030
Original poster
In case people missed it:
Yeah, it seems like you can now scale AirPlay resolution.
It'll still output to 1920 x 1080, but the effective (internal) resolution is 2560 x 1440, thus giving that much more desk space.