diff --git a/dom/crypto/CryptoBuffer.cpp b/dom/crypto/CryptoBuffer.cpp
index 95777d8b0895..20f76a45d497 100644
--- a/dom/crypto/CryptoBuffer.cpp
+++ b/dom/crypto/CryptoBuffer.cpp
@@ -17,13 +17,14 @@ CryptoBuffer::Assign(const CryptoBuffer& aData)
 {
   // Same as in nsTArray_Impl::operator=, but return the value
   // returned from ReplaceElementsAt to enable OOM detection
-  return ReplaceElementsAt(0, Length(), aData.Elements(), aData.Length());
+  return ReplaceElementsAt(0, Length(), aData.Elements(), aData.Length(),
+                           fallible);
 }
 
 uint8_t*
 CryptoBuffer::Assign(const uint8_t* aData, uint32_t aLength)
 {
-  return ReplaceElementsAt(0, Length(), aData, aLength);
+  return ReplaceElementsAt(0, Length(), aData, aLength, fallible);
 }
 
 uint8_t*
diff --git a/dom/media/MediaData.cpp b/dom/media/MediaData.cpp
index d5de3c8c9ab9..bcb0770bcfc2 100644
--- a/dom/media/MediaData.cpp
+++ b/dom/media/MediaData.cpp
@@ -654,7 +654,7 @@ MediaRawDataWriter::Replace(const uint8_t* aData, size_t aSize)
 
   // We ensure sufficient capacity above so this shouldn't fail.
   MOZ_ALWAYS_TRUE(mBuffer->ReplaceElementsAt(mTarget->mPadding, mTarget->mSize,
-                                             aData, aSize));
+                                             aData, aSize, fallible));
   mTarget->mSize = mSize = aSize;
   return true;
 }
diff --git a/dom/svg/DOMSVGPathSegList.cpp b/dom/svg/DOMSVGPathSegList.cpp
index 7b34f84a0351..0f7f445c0941 100644
--- a/dom/svg/DOMSVGPathSegList.cpp
+++ b/dom/svg/DOMSVGPathSegList.cpp
@@ -438,10 +438,9 @@ DOMSVGPathSegList::ReplaceItem(DOMSVGPathSeg& aNewItem,
   float segAsRaw[1 + NS_SVG_PATH_SEG_MAX_ARGS];
   domItem->ToSVGPathSegEncodedData(segAsRaw);
 
-  bool ok = !!InternalList().mData.ReplaceElementsAt(
-                  internalIndex, 1 + oldArgCount,
-                  segAsRaw, 1 + newArgCount);
-  if (!ok) {
+  if (!InternalList().mData.ReplaceElementsAt(internalIndex, 1 + oldArgCount,
+                                              segAsRaw, 1 + newArgCount,
+                                              fallible)) {
     aError.Throw(NS_ERROR_OUT_OF_MEMORY);
     return nullptr;
   }