chromium.launcher script does not terminate on Chromium exit

[Lothar Braun]

The chromium.launcher process stays alive after the browser and its processes terminated

This affects the following transitional package version (that points to a snap):

$ apt-cache policy chromium-browser
chromium-browser:
  Installed: 80.0.3987.163-0ubuntu1
  Candidate: 80.0.3987.163-0ubuntu1
  Version table:
 *** 80.0.3987.163-0ubuntu1 500
        500 http://de.archive.ubuntu.com/ubuntu focal/universe amd64 Packages
        100 /var/lib/dpkg/status

$ lsb_release -rd
Description: Ubuntu 20.04 LTS
Release: 20.04

Steps to reproduce:

1.) Ensure chromium is not running:

   $ ps aux | grep chromium | grep -v grep
   $

2.) Start chromium browser using the launcher
3.) Verify running processes:

$ ps aux | grep chromium | grep -v grep | awk '{print $11,$12}'
/snap/chromium/1105/usr/lib/chromium-browser/chrome--no-default-browser-check
/bin/sh/snap/chromium/1105/bin/chromium.launcher
/snap/chromium/1105/usr/lib/chromium-browser/chrome --type=zygote
/snap/chromium/1105/usr/lib/chromium-browser/chrome --type=zygote
/snap/chromium/1105/usr/lib/chromium-browser/chrome --type=gpu-process
/snap/chromium/1105/usr/lib/chromium-browser/chrome --type=utility
/snap/chromium/1105/usr/lib/chromium-browser/chrome --type=renderer
/snap/chromium/1105/usr/lib/chromium-browser/chrome --type=renderer
/snap/chromium/1105/usr/lib/chromium-browser/chrome --type=renderer

4.) Close chromium

5.) Check for lingering processes:

   $ ps aux | grep chromium | grep -v grep | awk '{print $11,$12}'

/bin/sh /snap/chromium/1105/bin/chromium.launcher

If you restart chromium multiple times, more launcher processes will linger around in the system.

My expectation would be that the launcher process terminates after the main chrome process is terminated.

[Olivier Tilloy (osomon)]

This is being tracked in bug #1864901.