This bug was fixed in the package libreoffice - 1:6.1.2-0ubuntu4
--------------- libreoffice (1:6.1.2-0ubuntu4) disco; urgency=medium
* Make LibreOffice under the LXQt desktop environment use the Breeze theme as the default (LP: #1799001).
-- Simon Quigley <email address hidden> Sat, 03 Nov 2018 16:08:28 -0500
This bug was fixed in the package libreoffice - 1:6.1.2-0ubuntu4
---------------
libreoffice (1:6.1.2-0ubuntu4) disco; urgency=medium
* Make LibreOffice under the LXQt desktop environment use the Breeze theme
as the default (LP: #1799001).
-- Simon Quigley <email address hidden> Sat, 03 Nov 2018 16:08:28 -0500