diff --git a/src/tui/tui-stream-assembler.ts b/src/tui/tui-stream-assembler.ts
index 302cc7acc1c..4c2fa5a7235 100644
--- a/src/tui/tui-stream-assembler.ts
+++ b/src/tui/tui-stream-assembler.ts
@@ -151,7 +151,7 @@ export class TuiStreamAssembler {
     const streamedDisplayText = state.displayText;
     const streamedTextBlocks = [...state.contentBlocks];
     const streamedSawNonTextContentBlocks = state.sawNonTextContentBlocks;
-    this.updateRunState(state, message, showThinking);
+    this.updateRunState(state, message, showThinking, { protectBoundaryDrops: true });
     const finalComposed = state.displayText;
     const shouldKeepStreamedText =
       streamedSawNonTextContentBlocks &&