We have to thing on how we can express a time slider in MapML. I suppose, it is part of the “controls” that can be activated or not. But, as soon as there is time involved, we need “time” in the URL template of tiles, so it need a new “input” describing the time dimension of the tiles:
So we should add “time” as one of the input
@ axis
values.
https://maps4html.org/MapML/spec/#the-input-element