So, the bug is that if one clicks on the pins on the map, before one has clicked on something interactive on the timeline area ( including the main display area, with arrows to the right/left ), the main area doesn't get updated to show the relevant pin's main-area content.
However, if one clicks on some interactive element on the timeline, only after that does clicking on the pins on the map trigger changes in the main display area.
Site where the issue has been seen: http://timemapper.okfnlabs.org/okfn/medieval-philosophers#7
So, the bug is that if one clicks on the pins on the map, before one has clicked on something interactive on the timeline area ( including the main display area, with arrows to the right/left ), the main area doesn't get updated to show the relevant pin's main-area content.
However, if one clicks on some interactive element on the timeline, only after that does clicking on the pins on the map trigger changes in the main display area.