Uninstalling libreoffice-kf5 and libreoffice-qt solved the problem for me
Dietmar
This is an automatic notification regarding your Bug report which was filed against the libreoffice-core package: #1019423: libreoffice-impress: starting by double click from dolphin results in 1 pixel wide window It has been closed by Rene Engelhard <rene@debian.org>. Their explanation is attached below along with your original report. If this explanation is unsatisfactory and you have not received a better one in a separate message then please contact Rene Engelhard <rene@debian.org> by replying to this email.