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()