Also known as: (t8n:)
A command that applies a built-in CSS transition to a hook as it appears.
(transition: "pulse")[Gleep!] makes the hook
[Gleep!] use the “pulse” transition
when it appears.
At present, the following text string will produce a particular transition:
All transitions are 0.8 seconds long, unless a (transition-time:) command is added to the command.