[imp] mail list not refreshing imp 6.2.1

[Per olof Ljungmark]

Horde 5.2.1 / imp 6.2.1

When set to update at regular intervals, changes to read/unread done in
another mail reader are only visible in the browser tab and "Inbox" in
the left column.

The mail list is NOT updated, not even if ones clicks the "Refresh"
button, browser tab and "Inbox" IS updated.

Tested on FF and Chrome on more than one account.

This is a change from 5.1.6/6.1.7 that we currently run in production
where all three places are properly updated.

Bug, intentional or error in our test setup?

Thanks,

//per