Still keeps complaining about invalid certificate hours after leaving the network with the captive portal
Yesterday I was briefly in a Wifi network with a captive portal. Currently I am at home where of course there is no captive portal. Still, I periodically see dozens of alerts (for each of my Nextcloud calendars and address books) about an invalid certificate. 
For now, killing evolution-source-registry has made those alerts go away, but this is a nuisance, both that obviously, a captive portal isn't recognized for what it is and that synchronisation isn't deferred until it is unlocked and the fact that these alerts keep popping up long after leaving the respective network.
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