I am uploading time-enabled feature classes of three urbanized area boundaries from Pro 2.8.3 to AGOL. They get on to "My Content" just fine. When I take a peek at the layers in map-viewer, it takes an incredibly long time to render, then the map completely freezes up when I try to edit settings related to time on the layer. Trying to identify if its user error or a bug.
I uploaded two other sets of layers drawn from the same data and with identical settings and date fields as far as I can tell, and these had no issues.