This is the whole reason to run one system on every screen. The tablet already does it when it gets a keyboard.
Plug the phone into a monitor and get the desktop
One system, every screen: the phone should become the desk when it has a desk.
USB-C to a display, keyboard and mouse pair, and the phone's session renders as the desktop layout. Same apps, same files.
Status
PlannedPlanned, which means a maintainer agreed it should happen and it is on the roadmap in the Next lane, targeting 1.7. See it on the roadmap. Votes and any attached bounty decide how fast it moves from there.
There is a bounty on this
Plug the phone into a monitor and get the desktop layout. The most-voted idea on the board.
Discussion
143 comments, oldest firstPlanned, and honestly it was going to happen anyway; the shell already switches layouts on the tablet. The hard parts are display hotplug on the phone kernels and making sure a call arriving does not steal the big screen. Targeting 1.7.
Pledged. If it works on the OnePlus 15 once that port lands, my desk gets simpler by one whole computer.
Tested the shell side on a tablet with an external monitor. Layout switch takes about a second. The phone side waits on the port.