Unfortunately this add-on blocks usage of web.de's Mail-Check add-on (https://produkte.web.de/mailcheck/#.suche.brandlink.mailcheck): when trying to login to one of the configured mail accounts only an empty tab comes up with title "Placeholder for extension post request - tmp ". Is there a way to disable this add-on for specific sites? When I disable Temp Containers all is fine. Fwiw: I use this in conjunction with Multi-account containers add-on.
Other than that seems to work fine.