Selecing PPA doesn't sometime respond to give a pop up message of typing password from "Software & Update " center

[Compiler]

a screen record will be uploaded to decribe this.

ProblemType: Bug
DistroRelease: Ubuntu 19.04
Package: ubuntu-release-upgrader-core 1:19.04.16.1
ProcVersionSignature: Ubuntu 5.0.0-13.14-generic 5.0.6
Uname: Linux 5.0.0-13-generic x86_64
ApportVersion: 2.20.10-0ubuntu27
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: ubuntu:GNOME
Date: Sat Apr 20 11:40:17 2019
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
Symptom: release-upgrade
UpgradeStatus: No upgrade log present (probably fresh install)
VarLogDistupgradeAptclonesystemstate.tar.gz:
 Error: command ['pkexec', 'cat', '/var/log/dist-upgrade/apt-clone_system_state.tar.gz'] failed with exit code 127: The value for the SHELL variable was not found the /etc/shells file

 This incident has been reported.
VarLogDistupgradeApttermlog: Error: [Errno 13] Permission denied: '/var/log/dist-upgrade/apt-term.log'