Created attachment 137682 [details] Output got in conjunction with the opening of an .odt document. Libreoffice help: Version: 5.3.7.2.0+ Build ID: 5.3.7.2-1.fc26 CPU Threads: 2; OS Version: Linux 4.11; UI Render: default; VCL: gtk3; Layout Engine: new; Locale: en-GB (en_GB.UTF-8); Calc: group On Fedora 26 $ uname -a Linux localhost.localdomain 4.11.8-300.fc26.x86_64 #1 SMP Thu Jun 29 20:09:48 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux From time to time opening an .odt document leads to an issue which is not tied to any particular document, as illustrated in the present attachment.
This is not a bug with LibreOffice, but rather just a problem in how you have MIME types/default applications configured. The document is opening in a different application, other than LibreOffice. See https://fedoramagazine.org/how-to-select-and-set-default-applications-in-fedora/ for help with this issue.