I upgraded on 13 Jul 2019 and calibre headers no longer sort the selected
items.
Clicking on the column header should sort by that selection. 
This is no longer working.

Name        : calibre
Version     : 3.44.0
Release     : 2.1
Architecture: x86_64
Install Date: Sat 13 Jul 2019 11:23:01 PM CDT
Group       : Productivity/Other
Size        : 58565819
License     : GPL-3.0-only
Signature   : RSA/SHA256, Mon 01 Jul 2019 06:34:47 AM CDT, Key ID
b88b2fd43dbdc284
Source RPM  : calibre-3.44.0-2.1.src.rpm
Build Date  : Mon 01 Jul 2019 06:33:27 AM CDT
Build Host  : cloud122
Relocations : (not relocatable)
Packager    : https://bugs.opensuse.org
Vendor      : openSUSE
URL         : https://calibre-ebook.com