Is it possible to manage the synonyms from file using Kibana?
I can not find it in the UI.
Can you elaborate what you want to do exactly?
If this is about the synonym token filter (https://www.elastic.co/guide/en/elasticsearch/reference/current/analysis-synonym-tokenfilter.html), then you can manage the settings to a certain degree in "Stack Management > Index management", but it won't allow you to change the contents of the synonym file.