Both languagetool.org and community.languagetool.org are currently down. I'm waiting for the hosting company to get the server running again.
The server is back online - total downtime was about 1.5 hours.
community.languagetool.org seems to have problems again (about 12:00 German time).
Fixed - there's a configuration issue causing community.languagetool.org (i.e. Tomcat) not to start properly after system reboot.