TreeView supports this, buttonbar has issues. Fixes issue 4061 Change-Id: If1f254caac4455a0c0f730ea4885f73de62bebec Reviewed-on: http://gerrit.dmdirc.com/1188 Reviewed-by: Chris Smith <chris@dmdirc.com> Automatic-Compile: DMDirc Local Commits <dmdirc@googlemail.com>