I'm using the PinePhone Beta with a recent Mobian weekly and Linux 5.15. I kept seeing the Mobian background image (geometric blue shapes) when I tried to use video out over Pine64's USB-C hub, but I couldn't see anything else. However, I plugged and unplugged the hub repeatedly, and then for some reason it suddenly worked. (I never got it to work with an HDMI to VGA converter for my monitor, but it does work with HDMI on my projector.)
In the quick access menu on the top, Phosh still says "undocked", but the external mouse and keyboard do work on the external screen. Most applications open in a maximized window that covers the entire screen and there is no option use them inside of a movable window. However, the King's Cross terminal, Calculator and Weather open by default inside a window and they can be moved and resized, so the same should be possible for the other apps, but I haven't figured out what gsetting allows this. Alt+Tab on the external keyboard can be used to switch applications, but I can't figure out how to get to a main menu to execute apps or get to the default launcher screen. If I close all the available apps, I just see the blue background image, but I can't do anything. The Phosh
documentation and
source code page provide no info on how to use Phosh in "docked" mode.
Any ideas?
OK, I figured out what is going on. When I dock with an external monitor, it defaults to the background image and it is only showing me the bottom right corner of the background image, so most of the screen is not being displayed on my external monitor. To get around this, I pressed Alt+Tab to switch to one of the open apps (which I can't see because it is on part of the screen which isn't being displayed on the external monitor. Then, I pressed Alt+F10 to maximize the app and now I can see it. Hooray!
You can maximize/unmaximize a window by pressing Alt+F10 or by double clicking on its title bar. When unmaximized, you can resize and move the window.
I still haven't figured out how to get to the start screen to start apps when using an external monitor, so I am having to use the PinePhone's screen to start apps. However, I found a work-around. I can press Alt+F2. I won't see the dialog box on the external monitor to enter a command, but I can type a command (like "kgx" or "firefox-esr") and then press ENTER, and then the app will appear on the screen. Sometimes I have to press Alt+F10 to see the app, but it works.