This is normal, because it is the Inbox and it defaults to show newest. If it did not do this then people would complain it is a bug. Thunderbird auto accesses server to check for new mail. So focus is on that action.

It is also a good idea to not store older emails in the Inbox and instead use it as an Inbox for new emails or those as yet not sorted/responded to etc. It is somewhat more risky to keep a lot of emails in the Inbox. It is also a good idea to compact the Inbox on a regular basis to remove old hidden marked as deleted emails. General info on how to maintain a healthy thunderbird:

• http://kb.mozillazine.org/Keep_it_working_%28Thunderbird%29
• http://kb.mozillazine.org/Thunderbird_:_Tips_:_Compacting_Folders

Thank you for your answer, Toad-Hall!

Unfortunately, it is the same with other folders, not only the inbox. If the folder contains more emails than can be displayed without scrolling, the end of the list (where the newest emails are) is displayed. Even if emails are sorted by date, oldest on top.

Summing up: No matter if messages are sorted from old to new or from new to old, you will always see the newest message first when opening the folder. That doesn't make much sense to me.

The sort method relates to the order of the list. Some people like to use the old original method of sorting with oldest at top, after all a list is created and appended with latest at the bottom, but they want focus on newest because the new incoming emails are more important on old. Otherwise they would need to continuously scroll to see new incoming mail. When this used to occur there was a hugely significant number of complaints requesting this to be fixed and always focus should be on new.

Most people now tend to sort with newest on the top as it is easy to locate the newest emails.

The 'sort by' has nothing to do with focus on newest.