Gnuplot Warning

How do you start gnuplot?

Changing the invocation command to
QT_QPA_PLATFORM=wayland gnuplot
may help.

After I entered "QT_QPA_PLATFORM=wayland gnuplot" in the terminal the following is coming.

Warning: Ignoring XDG_SESSION_TYPE=wayland on Gnome. Use QT_QPA_PLATFORM=wayland to run on Wayland anyway.
QSocketNotifier: Can only be used with threads started with QThread

What do you get for

XDG_SESSION_TYPE="" QT_QPA_PLATFORM=wayland gnuplot

Does gnuplot work despite showing the message or not?

After giving XDG_SESSION_TYPE="" QT_QPA_PLATFORM=wayland gnuplot it is showing the following. Gnuplot is working but the following message is coming.

QSocketNotifier: Can only be used with threads started with QThread

If the program works, why bother?

For diagnostic purposes please provide the output that you receive for the following commands:

uname -a
lsb_release -crid
apt policy gnuplot-qt qt6-wayland

uname -a

Linux partha-VivoBook-ASUSLaptop-X421EAY-X413EA 5.15.0-47-generic #51-Ubuntu SMP Thu Aug 11 07:51:15 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

lsb_release -crid

Distributor ID: Ubuntu
Description: Ubuntu 22.04.1 LTS
Release: 22.04
Codename: jammy

 apt policy gnuplot-qt qt6-wayland

gnuplot-qt:
  Installed: 5.4.2+dfsg2-2
  Candidate: 5.4.2+dfsg2-2
  Version table:
 *** 5.4.2+dfsg2-2 500
        500 http://in.archive.ubuntu.com/ubuntu jammy/universe amd64 Packages
        100 /var/lib/dpkg/status
qt6-wayland:
  Installed: (none)
  Candidate: 6.2.4-1
  Version table:
     6.2.4-1 500
        500 http://in.archive.ubuntu.com/ubuntu jammy/universe amd64 Packages

There are some comments on the internet that installing certain qt-wayland packages may help getting rid of the warning message.

Try the command
sudo apt install qtwayland5 qt6-wayland

If that doesn't help, then I recommend just ignoring the message. I do not see any harm being caused by it.