Why do the yellow tooltips appear even when Dashboard is closed?

This is a bug in Dashboard itself unfortunately. We've reported the problem to Apple and we're hoping they'll fix it. In the meantime, there is a hidden setting to disable the tooltips that show delivery details. Open Terminal, enter this on one line, then press return:
defaults write widget-com.junecloud.widget.deliverystatus disabletooltips 1; killall Dock;

To turn the tooltips back on, enter:
defaults delete widget-com.junecloud.widget.deliverystatus disabletooltips; killall Dock;

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