diff --git a/config/config.exs b/config/config.exs
index 59a6a4b6c..5087122da 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -189,7 +189,6 @@ config :mobilizon, Mobilizon.Service.Formatter,
 config :tesla, adapter: Tesla.Adapter.Hackney
 
 config :phoenix, :format_encoders, json: Jason, "activity-json": Jason
-config :phoenix, :json_library, Jason
 config :phoenix, :filter_parameters, ["password", "token"]
 
 config :absinthe, schema: Mobilizon.GraphQL.Schema