With June 2016's firmware update 7.2, "Enable selecting all resolutions" was abruptly removed from Platform Secret Screen > System Operations Menu. (Home 5x, FF, Play, RW, Play, FF) The capability still is in the hardware, but evidently the Roku powers-that-be are bound and determined not to reinstate user-access to it.
1) Do documented API hooks exist to "Enable selecting all resolutions" such that a simple one-trick pony channel might be dashed-off to turn it on? (I am not a programmer.)
2) Failing that, there at least used to be a way to telnet into a Roku's IP address on port 8085 to do things like sending remote control key-presses. Is there a telnet command to toggle "Enable selecting all resolutions"?
3) Failing that, is there such thing as a pre-v7.2 firmware installer, or in the form of a channel (if it even can work that way), to be side-loaded if necessary, to roll-back the firmware temporarily, just so we can set “Enable selecting all resolutions”? Of course we would promptly get auto-updated again, but we would have enough time to do the deed, and have the installer or channel on-hand if needed again.
4) Failing that, here’s an idea: Roku Support sets up a webpage to enter our Roku serial number and it pushes-out "Enable selecting all resolutions." This way, Roku retains complete control, and eliminates incentive for us to find a hack. Win-win, everybody happy!
Roku 3 (4200) purchased for $22.93 on clearance at Office Depot > Bleiden HDMI-to-Composite converter > old 4:3 CRT TV (now in another room, as I have acquired a modern LCD flat screen TV, March 2017)
R.I.P. Roku XD|S (2100), Feb 2011–Apr 2016