Timeline and TimelineSlider example code does not work

[metmets]

The example code shown in the Timeline and TimelineSlider page does not work. The map does not render on the user guide page, nor does it render when running it yourself.

Tried with Chrome, Edge and Firefox.

It appears to have broken when going from version 0.18.0 to 0.19.0.

[hansthen]

@metmets Thanks for notifying us.