diff --git a/config/settings.yml b/config/settings.yml
index bcf2bfb..b53d9b4 100644
--- a/config/settings.yml
+++ b/config/settings.yml
@@ -7,6 +7,12 @@ login:
   oauth2_authorize_url: ""
   oauth2_authorize_signup_url: ""
   oauth2_token_url: ""
+  oauth2_token_request_encoding:
+    default: "form_encoded"
+    type: enum
+    choices:
+      - form_encoded
+      - json
   oauth2_token_url_method:
     default: "POST"
     type: enum
diff --git a/plugin.rb b/plugin.rb
index c5e4dcb..f3ae231 100644
--- a/plugin.rb
+++ b/plugin.rb
@@ -51,9 +51,11 @@ def request(env)
     warn <<~LOG
       OAuth2 Debugging: request #{env.method.upcase} #{env.url.to_s}
 
-      Headers: #{env.request_headers}
+      Headers:
+      #{env.request_headers.to_yaml}
 
-      Body: #{env[:body]}
+      Body:
+      #{env[:body].to_yaml}
     LOG
   end
 
@@ -63,9 +65,11 @@ def response(env)
 
       From #{env.method.upcase} #{env.url.to_s}
 
-      Headers: #{env.response_headers}
+      Headers:
+      #{env.request_headers.to_yaml}
 
-      Body: #{env[:body]}
+      Body:
+      #{env[:body].to_yaml}
     LOG
   end
 end
@@ -121,9 +125,10 @@ def register_middleware(omniauth)
                             opts[:client_options][:auth_scheme] = :request_body
                             opts[:token_params] = {
                               headers: {
-                                "Authorization" => basic_auth_header,
+                                "Authorization" => basic_auth_header
                               },
                             }
+                            opts[:token_params][:headers]["Content-Type"] = "application/json" if SiteSetting.oauth2_token_request_encoding == "json"
                           elsif SiteSetting.oauth2_send_auth_header?
                             opts[:client_options][:auth_scheme] = :basic_auth
                           else
@@ -141,7 +146,8 @@ def register_middleware(omniauth)
                                                { bodies: true, formatter: OAuth2FaradayFormatter }
                             end
 
-                            builder.request :url_encoded # form-encode POST params
+                            encoding = SiteSetting.oauth2_token_request_encoding == "form_encoded" ? :url_encoded : :json
+                            builder.request encoding
                             builder.adapter FinalDestination::FaradayAdapter # make requests with FinalDestination::HTTP
                           end
                         }
@@ -223,19 +229,22 @@ def fetch_user_details(token, id)
     user_json_url = SiteSetting.oauth2_user_json_url.sub(":token", token.to_s).sub(":id", id.to_s)
     user_json_method = SiteSetting.oauth2_user_json_url_method.downcase.to_sym
 
-    log("user_json_url: #{user_json_method} #{user_json_url}")
-
     bearer_token = "Bearer #{token}"
     connection = Faraday.new { |f| f.adapter FinalDestination::FaradayAdapter }
     headers = { "Authorization" => bearer_token, "Accept" => "application/json" }
     user_json_response = connection.run_request(user_json_method, user_json_url, nil, headers)
 
-    log("user_json_response: #{user_json_response.inspect}")
+    log <<-LOG
+      user_json request: #{user_json_method} #{user_json_url}
+
+      response:
+      #{user_json_response.to_yaml}
+    LOG
 
     if user_json_response.status == 200
       user_json = JSON.parse(user_json_response.body)
 
-      log("user_json: #{user_json}")
+      log("user_json:\n#{user_json.to_yaml}")
 
       result = {}
       if user_json.present?
@@ -270,9 +279,23 @@ def always_update_user_email?
   end
 
   def after_authenticate(auth, existing_account: nil)
-    log(
-      "after_authenticate response: \n\ncreds: #{auth["credentials"].to_hash}\nuid: #{auth["uid"]}\ninfo: #{auth["info"].to_hash}\nextra: #{auth["extra"].to_hash}",
-    )
+    log <<-LOG
+      after_authenticate response:
+
+      creds:
+      #{auth["credentials"].to_hash.to_yaml}
+
+      uid: #{auth["uid"]}
+
+      info:
+      #{auth["info"].to_hash.to_yaml}
+
+      extra:
+      #{auth["extra"].to_hash.to_yaml}
+
+      all:
+      #{auth&.to_hash&.to_yaml}
+    LOG
 
     if SiteSetting.oauth2_fetch_user_details?
       if fetched_user_details = fetch_user_details(auth["credentials"]["token"], auth["uid"])