Same problem using Debian kde 5.23.5 with wayland. My libreoffice version is 7.3.1. A temporary solution is to set the environment variable QT_QPA_PLATFORM=xcb before running libreoffice. So the command is QT_QPA_PLATFORM=xcb libreoffice. And this will make the program work just fine. Anyway hope the developer fix the issue soon.
Same problem using Debian kde 5.23.5 with wayland. My libreoffice version is 7.3.1. A temporary solution is to set the environment variable QT_QPA_PLATFORM=xcb before running libreoffice. So the command is QT_QPA_PLATFORM=xcb libreoffice. And this will make the program work just fine. Anyway hope the developer fix the issue soon.