diff --git a/core/icons/comment_icon.ts b/core/icons/comment_icon.ts
index c05748dcc..064f67843 100644
--- a/core/icons/comment_icon.ts
+++ b/core/icons/comment_icon.ts
@@ -114,7 +114,7 @@ export class CommentIcon extends Icon implements IHasBubble, ISerializable {
       },
       this.svgRoot,
     );
-    dom.addClass(this.svgRoot!, 'blockly-icon-comment');
+    dom.addClass(this.svgRoot!, 'blocklyCommentIcon');
   }
 
   override dispose() {
diff --git a/core/icons/mutator_icon.ts b/core/icons/mutator_icon.ts
index 7fb3fcf3b..2c350f544 100644
--- a/core/icons/mutator_icon.ts
+++ b/core/icons/mutator_icon.ts
@@ -116,7 +116,7 @@ export class MutatorIcon extends Icon implements IHasBubble {
       {'class': 'blocklyIconShape', 'r': '2.7', 'cx': '8', 'cy': '8'},
       this.svgRoot,
     );
-    dom.addClass(this.svgRoot!, 'blockly-icon-mutator');
+    dom.addClass(this.svgRoot!, 'blocklyMutatorIcon');
   }
 
   override dispose(): void {
diff --git a/core/icons/warning_icon.ts b/core/icons/warning_icon.ts
index 08f511a60..5a22ec16d 100644
--- a/core/icons/warning_icon.ts
+++ b/core/icons/warning_icon.ts
@@ -89,7 +89,7 @@ export class WarningIcon extends Icon implements IHasBubble {
       },
       this.svgRoot,
     );
-    dom.addClass(this.svgRoot!, 'blockly-icon-warning');
+    dom.addClass(this.svgRoot!, 'blocklyWarningIcon');
   }
 
   override dispose() {