Fix crash if main window is closed #1692

Please select the right template in the above drop down box.

mentioned in issue #2620 (closed)

added 1stcontrib label

added bug label

changed milestone to %v1.4.21

changed milestone to %1.4.22

assigned to @antenore

Perfect, I'll update the authors list before the next release

mentioned in commit f3aeb38b

merged

mentioned in commit cdc0101e

mentioned in commit 2197e566

mentioned in merge request !2356 (merged)