Yesterday emails suddenly appeared Read; after changing a checkbox, all appear Unread; can't find a fix to make unread show unread and read show Read.
Everything was fine until midday 4/6. All read emails were in regular type, and all new and unread emails were in bold type, appearing UNread. Suddenly, all the emails appeared to be READ, even though many had not been. I followed some online instruction to uncheck the box that makes messages appear as read "immediately upon display," or "after _ seconds." Where is the place where READ emails are displayed as read after they're read and UNREAD emails continue to display unread? Baffling, especially because it has never happened before and I hate this.
Alle antwurden (1)
The option you are looking for is in Preferences > Display > Advanced. There you can set whether or not Thunderbird automatically changes the status of a message from 'read' to 'unread', and whether it does so immediately the message is opened or after a delay. If you want to manually change the status of messages in the list (from 'read' to 'unread' or vice versa) then highlight the entry/entries in the list and right click: the context menu has an option 'mark' (... as unread etc.)