PrintScreen key stops launching Spectacle after using it a few times in Bionic

[Pedro Gongora]

The PrintScreen hotkey only works some (randomly) few times, after that, pressing PrintScreen doesn't launch Spectacle anymore. Workarround: either restarting the session or pressing the combo Meta+PrintScreen makes it work again.

The number of times that PrintScreen works well before failing varies, however, I've found a way to consistently reproduce the bug.

Reproducible: Always

Steps to Reproduce:
1. Press PrintScreen to launch Spectacle
2. Click on "Save and quit" button to save the screenshot and launch a notification bubble
3. On the notification bubble press the "settings" button a the top right.
4. Simply click the "Cancel" button at the opened settings window and the PrintScreen hotkey will stop working

Expected result:
Pressing PrintScreen should launch Spectacle

Kubuntu 18.04 LTS on amd64
khotkeys 4:5.12.4-0ubuntu1

[Scarlett Gately Moore (scarlettmoore)]

I cannot reproduce on noble.