upgrade xubuntu from 18.04 LTS to 20.04 LTS

1, change source.list from bionic to focal

deb http://mirrors.163.com/ubuntu/ focal main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ focal-security main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ focal-updates main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ focal-proposed main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ focal-backports main restricted universe multiverse

deb-src http://mirrors.163.com/ubuntu/ focal main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ focal-security main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ focal-updates main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ focal-proposed main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ focal-backports main restricted universe multiverse

#deb https://dl.winehq.org/wine-builds/ubuntu/ focal main

2, upgrade to xubuntu 20.04 Focal

$sudo apt update
$sudo apt dist-upgrade

3, fix xubuntu 20.04 issues

(3.1) chrome browser issue

chromium-browser需要首先安装snap，改为直接下载并安装google-chrome

$sudo apt remove chromium-browser
$sudo apt autoremove --purge snapd
$wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb
$sudo apt install ./google-chrome-stable_current_amd64.deb

拷贝chromium-browser的配置信息

$cp -r ~/.config/chromium/* ~/.config/google-chrome/

(3.2) vmware kernel module updater issue

refer to https://blog.csdn.net/Aginouxy/article/details/104652991

(3.3) steam issue

$sudo apt install steam

(3.4) hibernate grayed issue

$su
#cd /etc/polkit-1/localauthority/50-local.d
#vim com.ubuntu.enable-hibernate.pkla
#reboot

contents of 'com.ubuntu.enable-hibernate.pkla': 

[Re-enable hibernate by default in upower]
Identity=unix-user:*
Action=org.freedesktop.upower.hibernate
ResultActive=yes

[Re-enable hibernate by default in logind]
Identity=unix-user:*
Action=org.freedesktop.login1.hibernate;org.freedesktop.login1.handle-hibernate-key;org.freedesktop.login1;org.freedesktop.login1.hibernate-multiple-sessions;org.freedesktop.login1.hibernate-ignore-inhibit
ResultActive=yes

(3.5) xfce4-screensaver issue, use xscreensaver by default

$sudo apt remove xfce4-screensaver

(3.6) wine issue (libncurses): 

Wine cannot find the ncurses library (libncurses.so.6).

$sudo apt install libncurses6:i386

(3.7) python3 3rd-party libraries

$pip3 install cx-Oracle jsbeautifier paramiko pyinstaller pyqt5==5.12.2 regex sqlparse xlsxwriter