First up, LibreOffice has switched from using GLEW to Epoxy. GLEW, of course being the OpenGL Extension Wrangler Library. Epoxy, meanwhile, being the newer library for handling OpenGL function pointer management with GLX/WGL/EGL support, OpenGL ES 1/2/3, and OpenGL 4.4 core/compatibility support.
LibreOffice has switched from GLEW to Epoxy due to it working under Wayland "out of the box" and GTK3 using it. More details via Gerrit. The work was done by Red Hat.
Another change by Red Hat's Caolán McNamara is OpenGL support for LibreOffice slideshows when using the LO GTK3 code.
In recent days have also been some other Wayland changes, mainly addressing fixes for this open-source office suite.