diff --git a/black-browser.js b/black-browser.js
index 8d692cd..75fdef1 100644
--- a/black-browser.js
+++ b/black-browser.js
@@ -242,6 +242,9 @@ class RequestProcessor {
           if (bodyObj.generationConfig?.thinkingConfig) {
             delete bodyObj.generationConfig.thinkingConfig;
           }
+          if (bodyObj.generationConfig?.responseModalities) {
+            delete bodyObj.generationConfig.responseModalities;
+          }
         }
 
         config.body = JSON.stringify(bodyObj);