I have recently had a need to ‘save as’ messages for embedment in a spread sheet. I’ve found that if I right click on the actual message, and select ‘save as’ I get what I think is a normal dialog box. If however I right click on the message in the message list, and select ‘save as’ there, the popup asks what folder it should put it in, but does not ask for filename - it does the save, and assigns an arbitrary file name to it. Just a bit of a bug…
Not a bug.
The reason why right-click in the message list only asks for a folder and not a file name is because it is a list of conversations not messages. So this will save all the messages in that conversation in the folder you selected. If you turn off conversations in Menu > View > Conversations, then it reverts to a list of messages and the dialogue you require.
The file name is not arbitrary, it is the date the message was received followed by the subject.