Don't remove links when html signature is converted to text (#1489621)
Fix so when switching editor mode original version of signature is used (#1488849)
Define common styles for search boxes
Fix incorrect handling of HTML comments in messages sanitization code (#1489904)
Fix wrong set-listmode command (button) status set by getunread request
Fix so current page is reset on list-mode change (#1489907)
Limit cache data size to avoid database errors
Don't list empty (nil) metadata entries to save memory anc caching space