X11 copy and paste with mouse is broken

[keinstein]

Please include:

1. detailed steps on how to reproduce the bug, preferably with already
   existing JUCE code such as the demo plugin or the demo code

• Run DemoRunner

• Activate the CodeEditor demo

• Open a another window like a shell or emacs or any other program

• Use the left mouse button to select some text in the CodeEditor

• Move the mouse to the shell or Emacs window

• klick the middle mouse button

• Try the same procedure to copy and paste text from any X11 program to any other X11 program
  2) the expected behaviour
  The marked text is pasted into the shell or Emacs window.
  3) the operating system
  Linux
  4) the architecture (32-bit or 64-bit)
  64bit
  5) a stack trace - if the bug causes a crash
  no crash no trace
  6) the plugin format (VST2, VST3, AU, AAX, RTAS) - if applicable
  not applicable
  7) which DAW you observed the bug in - if applicable
  not applicable

Note that copy and paste without keyboard interaction is one of the important productivity features of X11.

[tpoole]

Is this using the develop branch, which includes 06db7f0?

I can't reproduce the issue on the develop branch, using 64-bit Ubuntu 20.04.3 LTS 5.11.0-36-generic, pasting into Terminal or Text Editor.

[keinstein]

I have included that patch manually without useful result (Debian testing x86_64).

[tpoole]

OK, I can reproduce the issue now. Looks like something was going amiss with my VM and a virtual mouse. Plugging in a hardware mouse shows the problem.