2 sets of Language Source

when I switch from one prefab to another, the filter switches from Everything to Nothing automatically

That was happening because the select categories remain the same when switching language sources. And if both sources have different categories, then it will filter out each other.

That isn't very intuitive, so I changed the code to handle that case.
Now when switching between different LanguageSources, the categories filter is set to "Everything"

The new changes can be found in v2.6.10a5 which I just uploaded to the beta folder.
Hope that helps,
Frank