** Package changed: unity-settings-daemon (Ubuntu) => lightdm (Ubuntu)

** Package changed: lightdm (Ubuntu) => lightdm

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https://bugs.launchpad.net/bugs/1848849

Title:
  Lightdm fails to undo quoting for Exec key

Status in Light Display Manager:
  New

Bug description:
  According to spec/documentation, "implementations must undo quoting
  before expanding field codes and before passing the argument to the
  executable program."

  https://developer.gnome.org/desktop-entry-spec/#exec-variables

  lightdm fails to do so and passes the double-quote characters to the
  executable program.

  Consider the following files:

  myecho:
  #!/bin/bash
  echo "$1" > /tmp/cmd

  /usr/share/xsessions/test.desktop:
  [Desktop Entry]
  Name=Test
  Comment=This is a test session
  Type=Application
  Exec=myecho "argument"

  myecho is to be located somewhere in the PATH.

  When trying to start a desktop session defined by test.desktop, as a
  result of running myecho, the first command-line argument from the
  Exec is written to /tmp/cmd.

  Here is where lightdm is wrong: Starting the 'test' session under
  lightdm causes '"argument"' (without the surrounding single quotes) to
  be written to /tmp/cmd. The correct string should be 'argument'
  (without the surrounding single quotes). If the double-quotes are
  removed from the Exec line, lightdm behaves normally and 'argument' is
  written.

  A practical consequence of this bug is that users can't use "bash -c"
  to run multiple commands when special characters (including spaces)
  are needed in the argument after "-c". It seems that the user must
  resort to a wrapper script because of this bug.

  $ lsb_release -rd
  Description:  Ubuntu 19.04
  Release:      19.04

  $ apt-cache policy lightdm
  lightdm:
    Installed: 1.28.0-0ubuntu1
    Candidate: 1.28.0-0ubuntu1
    Version table:
   *** 1.28.0-0ubuntu1 500
          500 http://mirrors.yun-idc.com/ubuntu disco/universe amd64 Packages
          100 /var/lib/dpkg/status

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