Forum topics do not show in french or show multiple times in french

Issue Summary

Hello,

in my multilingual website I have forums.

First I did not switch on multilingual for the forums. My setting is that content shows in current language (if available) or default language or language neutral.

With this setting, forum entries showed in german and english, but not in french.

Then I switched on multilingual for forum entries. After this, still no entries in french. Then I changed the language of one entry from english (default) to language neutral.

This resulted in this entry showing nine times when setting current language to french, whereas everything worked fine when setting language to german.

You can view this behaviour at raumgeometrie.de

Regards,

Andreas