diff --git a/src/browser/RenderDebouncer.ts b/src/browser/RenderDebouncer.ts
index f6ea59bf6..fcfdaa5ec 100644
--- a/src/browser/RenderDebouncer.ts
+++ b/src/browser/RenderDebouncer.ts
@@ -23,7 +23,7 @@ export class RenderDebouncer implements IRenderDebouncerWithCallback {
   }
 
   public dispose(): void {
-    if (this._animationFrame) {
+    if (this._animationFrame !== undefined) {
       this._coreBrowserService.window.cancelAnimationFrame(this._animationFrame);
       this._animationFrame = undefined;
     }
@@ -31,7 +31,7 @@ export class RenderDebouncer implements IRenderDebouncerWithCallback {
 
   public addRefreshCallback(callback: FrameRequestCallback): number {
     this._refreshCallbacks.push(callback);
-    if (!this._animationFrame) {
+    if (this._animationFrame === undefined) {
       this._animationFrame = this._coreBrowserService.window.requestAnimationFrame(() => this._innerRefresh());
     }
     return this._animationFrame;
@@ -46,7 +46,7 @@ export class RenderDebouncer implements IRenderDebouncerWithCallback {
     this._rowStart = this._rowStart !== undefined ? Math.min(this._rowStart, rowStart) : rowStart;
     this._rowEnd = this._rowEnd !== undefined ? Math.max(this._rowEnd, rowEnd) : rowEnd;
 
-    if (this._animationFrame) {
+    if (this._animationFrame !== undefined) {
       return;
     }