In version index 39.0.4, built 2023-06-07, 08:48, I might have found a bug: when model information element is clicked and displayed, the timeline disappears, but when the information element is closed, the timeline is not drawn back. When the web page is refreshed, timeline is back.
Tested on Firefox ver. 114.0 and Google Chrome ver. 114.0.5735.110, both 64x versions!