[MlMt] Column customization works intermittantly

[Benjamin Coddington]

Hi list, I'm new here.

I'm using MailMate 1.9.4 (5234), and it is very helpful for me to be 
able view a column that shows either a message's list-id header, or a 
concatenation of some headers from bugzilla.  I do that with the 
following file:

~/Library/Application 
Support/MailMate/Resources/MmMessagesOutlineView/outlineColumns.plist:
{
     columns = {
         "identifier" = {
             title = "List-Id";
             sortKey = "list-id.identifier";
             formatting = {
                 formatString = "${list-id.identifier}";
                 placeholderString = "";
             };
         minimumWidth = 10;
         };

         "bugzilla-status" = {
             title = "BZ Status";
             sortKey = "X-Bugzilla-Status";
             formatting = {
                 formatString = 
"${X-Bugzilla-Status:+${X-Bugzilla-Status} }";
                 placeholderString = "";
             };
         };

         "bugzilla-assigned" = {
             title = "BZ Assigned";
             sortKey = "X-Bugzilla-Assigned-To";
             formatting = {
                 formatString = 
"${X-Bugzilla-Assigned-To:+${X-Bugzilla-Assigned-To} }";
                 placeholderString = "";
             };
         };

         "list_bz_meta" = {
             title = "List-Id or BZ Info";
             sortKey = "list_bz_meta";
             formatting = {
                 formatString = 
"${list-id.identifier}${X-Bugzilla-Status:+${X-Bugzilla-Status} for 
${X-Bugzilla-Assigned-To}}";
                 placeholderString = "";
             };
         };
     };
}

The list_bz_meta is the column I'd like to use.  This column always 
functions as expected for some period of time after starting MailMate 
(an hour or so), however at some point it will transition to a state 
where it will not show any text for newly arriving messages.  Restarting 
MailMate fixes it up again.

I've turned up the logging, nothing seems relevant other than: "Warning: 
Unknown field parser 'list-id.body'" at startup or when viewing an 
outline for a mailbox for the first time.  That message is still output 
even if I remove my outlineColumns.plist file entirely.

Any tips about how I might get this column to work reliably?

Thanks for any help,
Ben