User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; fr; rv:1.8.1.1) Gecko/20061204 Firefox/2.0.0.1 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; fr; rv:1.8.1.2pre) Gecko/20070116 Thunderbird/2.0b2 ID:2007011615 When using the new "back" and "forward" functions (bug 74959), if the target message is in a different folder that is set to view unread messages (or threads with unread messages), the target message should be displayed despite the fact that it is no longer unread. Reproducible: Always Steps to Reproduce: 1. Select unread messages view 2. Read one or more messages 3. Move to another folder, read another message 4. Activate "back" function Actual Results: The target folder is correctly selected but the message is not displayed (because it is not unread). Expected Results: The message should be displayed, overriding the unread view setting.

Agreed, anything else would be quite futile.

Still repro. I selected the unread filter from the filter bar and activated the pin icon so it preserves the filter settings. I used Next/Previous from Go menu. Thunderbird 52.1.0 (32-bit) Windows 7 64-bit