If you have a folder open in another tab and hit the Quickfolder button for
that folder, Thunderbird switches to that tab - great behavior!

If you open a message in the Reading List, this causes Thunderbird to open the
target folder in the current tab, even if the target tab is already open in
another tab - as above.

Should switch, as it does in the first scenario.

Makes sense - accepted.

Just clarified the title for now.

Created an attachment (id=8374) [details]
4.9 prerelease 102

This does it, I think. strangely I had implemented this for both Postbox and
SeaMonkey but omitted the code  in Tb where i call

MailUtils.displayMessageInFolderTab(..)

for navigating to the email. (The other 2 platforms use gDBView.selectMsgByKey)

Implemented in version 4.9.0