I am using The Bat! 8.2.4 but this has happened since I started using the application. I use IMAP with two email accounts (different servers) and POP with another email account/server.  I have a fairly large number of filters (30-50) which moves messages from my inbox into subfolders of my choosing (not sure all are virtual, but some are--they are not Analyzer's automated virtual folders).  When I open the application, The Bat! starts checking for email and loading them in my inbox.  I see one that I would like to know the contents, so I double click on it.  I start to read the message, but then, because of the filtering, the inbox gets smaller and the focus of the inbox on the message I'm trying to read changes to another message.  This gets reflected in the separate window I opened to view the message!  So instead of the important and timely message I wanted to finish, I now see a SPAM or irrelevant message from another sender.

I have to sit and wait for The Bat! filtering to be mostly done before I can open and read a message in its entirety.

Why can't the separate viewing window be de-linked from the changed focus of the main window?  Or why can't the focus of the main window be maintained (at least as long as the message I'm trying to view is not being filtered and moved)?

This is not a fatal flaw, but it is REALLY annoying.