Description of problem:
I tried to add a Google calendar to GNOME Calendar:
* I selected the calendar icon at the top right.
* I selected Calendar Settings
* I clicked Add | From Web...
* I enterend the Calendar Address in the form of: https://www.google.com:443/calendar/dav/my.username@gmail.com/events
* The "Enter your credentials" box popped up
* I entered my credentials
* clicked Connect
=> this crash happened.

Version-Release number of selected component:
gnome-calendar-3.32.2-1.fc30

Additional info:
reporter:       libreport-2.10.0
backtrace_rating: 4
cmdline:        /usr/bin/gnome-calendar --gapplication-service
crash_function: discover_sources_cb
executable:     /usr/bin/gnome-calendar
journald_cursor: s=d31af75972d4474c81efde7d6d020f40;i=32c9;b=992fbbcd0b7f4efc8e9869a91e1ed4cc;m=49510e9ae;t=58acca359678f;x=6fda62909aff2f42
kernel:         5.1.6-300.fc30.x86_64
rootdir:        /
runlevel:       N 5
type:           CCpp
uid:            1000

Truncated backtrace:
Thread no. 1 (5 frames)
 #0 discover_sources_cb at ../src/gcal-source-dialog.c:1545
 #1 g_task_return_now at ../gio/gtask.c:1209
 #2 complete_in_idle_cb at ../gio/gtask.c:1223
 #7 g_main_context_iteration at ../glib/gmain.c:3988
 #8 g_application_run at ../gio/gapplication.c:2516

Potential duplicate: bug 1287073