How do I enable ‘minimize on click’ on Ubuntu dock

Open Terminal and run

gsettings set org.gnome.shell.extensions.dash-to-dock click-action 'minimize'

To revert to the default option, simply run

gsettings reset org.gnome.shell.extensions.dash-to-dock click-action

How to make dock background 80% transparent in Ubuntu

First enable custom colors:

gsettings set org.gnome.shell.extensions.dash-to-dock transparency-mode 'FIXED'

Then, to set transparency to 80%, issue the command

gsettings set org.gnome.shell.extensions.dash-to-dock background-opacity 0.2

Change 0.0 to any number between 0 and 1.

To reset to the default setting:

gsettings reset org.gnome.shell.extensions.dash-to-dock background-opacity

Create a wallpaper slideshow using bash script and cron

Save this script as a bash file, update the DIR variable to point to your photo collection and schedule it with a cronjob.

#!/usr/bin/env bash

# Update the DIR variable to point to your photos

DIR="/home/masoko/Pictures/wallpapers/reddit"
PIC=$(ls $DIR/* | shuf -n1)

RUID=$(who | awk 'FNR == 1 {print $1}')
RUSER_UID=$(id -u ${RUID})
sudo -u ${RUID} DBUS_SESSION_BUS_ADDRESS="unix:path=/run/user/${RUSER_UID}/bus" gsettings set org.gnome.desktop.background picture-uri "file://$PIC"
exit