diff --git a/dom/canvas/WebGL2Context.cpp b/dom/canvas/WebGL2Context.cpp
index 635f1d56a95..fb6b4a39588 100644
--- a/dom/canvas/WebGL2Context.cpp
+++ b/dom/canvas/WebGL2Context.cpp
@@ -141,15 +141,11 @@ WebGLContext::InitWebGL2()
     gl->GetUIntegerv(LOCAL_GL_MAX_UNIFORM_BUFFER_BINDINGS,
                      &mGLMaxUniformBufferBindings);
 
-    mBoundTransformFeedbackBuffers =
-        MakeUnique<WebGLRefPtr<WebGLBuffer>[]>(mGLMaxTransformFeedbackSeparateAttribs);
-    mBoundUniformBuffers =
-        MakeUnique<WebGLRefPtr<WebGLBuffer>[]>(mGLMaxUniformBufferBindings);
+    mBoundTransformFeedbackBuffers.SetLength(mGLMaxTransformFeedbackSeparateAttribs);
+    mBoundUniformBuffers.SetLength(mGLMaxUniformBufferBindings);
 
     mDefaultTransformFeedback = new WebGLTransformFeedback(this, 0);
     mBoundTransformFeedback = mDefaultTransformFeedback;
-    auto xfBuffers = new WebGLRefPtr<WebGLBuffer>[mGLMaxTransformFeedbackSeparateAttribs];
-    mBoundTransformFeedbackBuffers.reset(xfBuffers);
 
     mBypassShaderValidation = true;
 
diff --git a/dom/canvas/WebGLContext.cpp b/dom/canvas/WebGLContext.cpp
index b7655d2a4c3..ff74e021ddf 100644
--- a/dom/canvas/WebGLContext.cpp
+++ b/dom/canvas/WebGLContext.cpp
@@ -342,14 +342,8 @@ WebGLContext::DestroyResourcesAndContext()
     mBoundTransformFeedback = nullptr;
     mDefaultTransformFeedback = nullptr;
 
-    if (mBoundTransformFeedbackBuffers) {
-        for (GLuint i = 0; i < mGLMaxTransformFeedbackSeparateAttribs; i++) {
-            mBoundTransformFeedbackBuffers[i] = nullptr;
-        }
-    }
-
-    for (GLuint i = 0; i < mGLMaxUniformBufferBindings; i++)
-        mBoundUniformBuffers[i] = nullptr;
+    mBoundTransformFeedbackBuffers.Clear();
+    mBoundUniformBuffers.Clear();
 
     while (!mTextures.isEmpty())
         mTextures.getLast()->DeleteOnce();
diff --git a/dom/canvas/WebGLContext.h b/dom/canvas/WebGLContext.h
index fc7fb718258..d4a92637158 100644
--- a/dom/canvas/WebGLContext.h
+++ b/dom/canvas/WebGLContext.h
@@ -926,8 +926,8 @@ protected:
     WebGLRefPtr<WebGLBuffer> mBoundTransformFeedbackBuffer;
     WebGLRefPtr<WebGLBuffer> mBoundUniformBuffer;
 
-    UniquePtr<WebGLRefPtr<WebGLBuffer>[]> mBoundUniformBuffers;
-    UniquePtr<WebGLRefPtr<WebGLBuffer>[]> mBoundTransformFeedbackBuffers;
+    nsTArray<WebGLRefPtr<WebGLBuffer>> mBoundUniformBuffers;
+    nsTArray<WebGLRefPtr<WebGLBuffer>> mBoundTransformFeedbackBuffers;
 
     WebGLRefPtr<WebGLBuffer>& GetBufferSlotByTarget(GLenum target);
     WebGLRefPtr<WebGLBuffer>& GetBufferSlotByTargetIndexed(GLenum target,