Luckily, adding a reporter is fairly simple. One can create a ~/.config/urlwatch/hooks.py script, e.g. with the contents below (using kdialog command line tool to display a message).
@WPalant setting DISPLAY=0 makes assumptions about the system that may not be true, i.e. the user running cron owning the X11 display.
@renalcalculus Sure, this is a simplification. But I think that anybody who will actually attempt to follow these steps will know if the underlying assumptions aren't right for them.
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