2

Whenever I use an external monitor ( Dell HD, same as in-built ) I get this annoying screen selection popup which I cannot make go away. Is there any particular process I can " Stop / Kill " to make this popup from flashing all the time ? I am using 20.04

enter image description here

user227495
  • 4,089
  • 17
  • 56
  • 101
  • 1
    Screen Selection Popup.. When it appears and when you select one of the option is it still appears?? – PRATAP Dec 07 '20 at 02:34
  • 1
    External monitor connected to laptop or desktop? Where is the popup appearing on native monitor/screen? Without choosing the option what would you like it to happen? "Mirror" "Join Displays" "External Only" "Built in Only"?? – PRATAP Dec 07 '20 at 02:42
  • @UnKNOWn , 1. No matter what I select, it continues to flash. 2. External monitor connected to laptop through HDMI 3. Popup is appearing on both laptop and external monitor. An interesting fact is that the flash sometimes selects the choice randomly by itself and the popup behave according to the selection. I even chose an option through Settings, and then Apply, it is no honoured and flashing continues. 4. I would prefer to stay with " Mirror " if possible. Thanks. – user227495 Dec 07 '20 at 02:49
  • I think there is a hardware problem with the HDMI Cable or ports.. Did you try to use another HDMI cable? – PRATAP Dec 07 '20 at 03:00
  • 1
    Also try to first connect the HDMI cable and then try to turn on both laptop and external monitor just to confirm this problem appears when laptop is on and you are connecting external monitor.. – PRATAP Dec 07 '20 at 03:02
  • I get this error on Kubuntu desktop as well which I choose through login option. But when I kill the process " Kscreen2 ", the flashing goes away and I am using that to do my work on this laptop because I do not know which process to kill in default Desktop. – user227495 Dec 07 '20 at 03:06
  • External monitor is connected all the time through HDMI. I have until now rebooted some 200 times and it works well on Kubuntu DE but not on Gnome ( default ) DE. Thanks. – user227495 Dec 07 '20 at 03:07
  • 1
    Oh ok.. So External Monitor is always connected. When you turn on laptop when external monitor is also turned on at login screen is it OK? Once you enter to GNOME DE whats the case?? – PRATAP Dec 07 '20 at 03:10
  • Once I get into Gnome/ default the popup appears and flashing starts. It chooses something by itself Sometimes external monitor goes black other time laptop monitor goes black according to which option the prompt choose by itself. Yes, both laptop and monitor gets power input at the same time and I keep the cable connecting laptop and external monitor as is. – user227495 Dec 07 '20 at 03:19
  • 2
    I dont know if you got past this point yet, but If identifying the process will help... do something like ps -eo pid,command >> withoutproblem.txt and ps -eo pid,command >> withproblem.txt then do a diff on the problem.txt files.... also pstree shows a tree of the parent processes, could be helpful. – WU-TANG Dec 07 '20 at 05:56
  • I will try and update. Thansk @WU-TANG – user227495 Dec 07 '20 at 06:50
  • If you use xrandr to set your display settings, does it turn it off? That's pretty much what the GUI triggers anyway... Also, does the hotkey cancel it? <Super+P> ... if it helps it helps any these are related: org.gnome.mutter.keybindings switch-monitor ['p', 'XF86Display'].... and com.canonical.unity.settings-daemon.plugins.media-keys video-out 'p' ..... I don't know how to back-trace to the thing that these are calling, maybe you or someone else will. When I use the selector and make it go crazy on my screen, only "gnome-shell's" CPU usage spikes in top. – WU-TANG Dec 10 '20 at 10:18
  • Thanks for telling me about Super + P. But it does not hold either. The whole blinking process continues even after I make a selection through Super + P. I checked for xrandr in system monitor so that I could kill it. But sadly, there are no matching entries in search result. The only thing that allows me to use Ubuntu is closing the laptop lid and use the external monitor alone. Appreciate all the help and advice. – user227495 Dec 10 '20 at 10:43
  • @user227495 ...what I meant, was try actually setting your displays with xrandr. Maybe doing what it's trying to accomplish will make it go away. A simple xrandr command would be xrandr --output HDMI-0 --auto --verbose --output HDMI-1 --auto --right-of HDMI-0...of course you have to use your own display connection names, they can be viewed by xrandr --verbose or xrandr --current for less detail... By the way, did you look at syslog??? maybe tail -f /var/log/syslog and see if a message is being thrown while the problem is happening... Maybe look at the Xorg.log – WU-TANG Dec 10 '20 at 11:54

1 Answers1

0

You should report it as a bug on your window manager project page, along with your dmesg output.(Assuming it's not your cable that's broken and constant reconnections triggering this... in that case, get a new cable!)

You can also try this How do I enable and disable GNOME extensions from the command line?

If you don't figure it out, or while you wait for a fix, you can use a different window manager:

sudo apt install gnome-flashback

or

sudo apt install xfce4

or

sudo apt install plasma-desktop

or

sudo apt install cinnamon

or

sudo apt install lxde

or... if you really want to get to know your system

sudo apt install wmaker

or

sudo apt install icewm

Select our window manager from the login screen by clicking on the small Ubuntu icon

Dagelf
  • 1,245
  • 1
    I do have Plasma. The same problem occurs there and I can stop by killing the process Kscreen2. I am trying to find what to kill in default DE. Thanks. – user227495 Dec 09 '20 at 03:07