diff -up cura-lulzbot-3.6.21/cura_app.py.force-x11 cura-lulzbot-3.6.21/cura_app.py

--- cura-lulzbot-3.6.21/cura_app.py.force-x11	2019-12-19 09:00:06.192165885 -0500

+++ cura-lulzbot-3.6.21/cura_app.py	2019-12-19 09:00:21.823877854 -0500

@@ -41,6 +41,8 @@ import faulthandler

 #WORKAROUND: GITHUB-88 GITHUB-385 GITHUB-612

 if Platform.isLinux(): # Needed for platform.linux_distribution, which is not available on Windows and OSX

+    # Workaround for invisible window on Wayland and (at least) Fedora 31

+    os.environ["XDG_SESSION_TYPE"] = "x11"

     # For Ubuntu: https://bugs.launchpad.net/ubuntu/+source/python-qt4/+bug/941826

     # linux_distro_name = platform.linux_distribution()[0].lower()