The space bar does not always advance to the next unread message
When I press the space bar whilst reading a message Thunderbird advances a page at a time through the message. When it comes to the end of the message pressing the space bar sometimes takes me to the next unread message. However, in some messages, pressing the space bar does not take me to the next unread message, rather I stay at the bottom of the message I have just read.
Opaite Mbohovái (1)
Here, with TB 60.8/W10, the space bar never moves to the next message, and the same in TB 69b4.
https://bugzilla.mozilla.org/show_bug.cgi?id=1468925
Until the bug receives some attention, use F and B to move forward and back through the messages (works for the Message Pane, tabs and windows).
Correction: the space bar does move to the next unread message, but not to the next message if it's read.
Moambuepyre