It has been 7 days since the last response to the thread and I received no further complaints, so I've put the criterion into effect:
It turns out I've not included "system settings" app, which was agreed to be important when discussing this bug:
So, here's a proposal to include:
* system settings
in the list of applications we block on. A particular example would be gnome-control-center.
Please voice your opinion. This should be fairly non-controversial, so unless somebody finds a good reason to omit it or phrase it differently, I'll make the change live in a day or two.