About language detect

Hi sorry to disturb,
I have a question about fess.
Does fess use standard analyzer for all indexed document?
or detect a proper language for a document before, and use different anaylazer for each document ?

I try fess 12.4 before, and learn about this feature from https://github.com/codelibs/elasticsearch-langfield, but this plugin not be used in 13.4 any more

Language detection moves into Fess as tika-langdetect.
For analyzers, please see fess.json.