diff --git a/polygerrit-ui/app/api/diff.ts b/polygerrit-ui/app/api/diff.ts
index 7ee68b7..39a4441 100644
--- a/polygerrit-ui/app/api/diff.ts
+++ b/polygerrit-ui/app/api/diff.ts
@@ -174,8 +174,6 @@
   font_size: number;
   // TODO: Missing documentation
   show_file_comment_button?: boolean;
-  // TODO: Missing documentation
-  theme?: string;
 }
 
 export declare interface RenderPreferences {
diff --git a/polygerrit-ui/app/constants/constants.ts b/polygerrit-ui/app/constants/constants.ts
index 03d5000..d78b3cd 100644
--- a/polygerrit-ui/app/constants/constants.ts
+++ b/polygerrit-ui/app/constants/constants.ts
@@ -416,7 +416,6 @@
     show_whitespace_errors: true,
     syntax_highlighting: true,
     tab_size: 8,
-    theme: 'DEFAULT',
   };
 }
 
diff --git a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface_test.js b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface_test.js
index fbd675f..8c29c2f 100644
--- a/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface_test.js
+++ b/polygerrit-ui/app/elements/shared/gr-rest-api-interface/gr-rest-api-interface_test.js
@@ -409,7 +409,6 @@
       assert.equal(obj.show_whitespace_errors, true);
       assert.equal(obj.syntax_highlighting, true);
       assert.equal(obj.tab_size, 8);
-      assert.equal(obj.theme, 'DEFAULT');
     });
   });