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It works excellent for me, God bless you!
Because I do not like to add adhoc packages, I've tested using this recepie.
Add Bionic Beaver Repository (18.04 LTS)
# add-apt-repository 'deb http://archive.ubuntu.com/ubuntu bionic main universe'
Install Missing package
# apt install -t bionic libwebkitgtk-1.0-0
Tested with sucess with PS Client 9.1R4 in a clean installation of Ubuntu 20.04