Today I Learned ...

Add space block in Mac Dock

To add a spacer block in Mac Dock …

defaults write com.apple.dock persistent-apps \
  -array-add '{"tile-type"="spacer-tile";}' \
  && killall Dock

You can change the list bullet icon from the conventional disc (or circle) to anything you want using either the marker property of the li tag:

li::marker {
  content: "\2192  "; /* Unicode for right arrow (→) */
}

or using the list-style-type property of the ul tag:

ul {
  list-style-type: "\2192  ";
}