With includeHashInUrl = true (a single page app) the cursor does not update across clients when the hash changes.
Reproduce by changing the location.hash via an Anchor click in one client, e.g. <a href=#newhash>. The other client follows. The follower loses the other client's cursor tracking message display.
Another case seems to be if the follower is idle for a little time then the cursors doesn't show at all on either side.
If I start both clients on the same url#hash then the cursor seems to work great. But once you change location in one client and follow in the other, the cursor stops showing.
There is a related issue where the editing of a textarea also stops working. The textarea will highlight showing that the other client is "in the box" but I don't see the other client's typing nor it's cursor display.
The session is still valid because the clients still receive each other's messages, for example, the follow prompt shows up and the textarea will highlight with the other client's color.
A workaround, albeit an unacceptable one, is to reload the page when the location.hash changes. In this case, all works as expected.
Another observation on this issue: the sameUrl value of the In Object is false, when in fact they are exactly the same.