diff --git a/docshell/base/nsDocShell.cpp b/docshell/base/nsDocShell.cpp
index e0622aa74844..0601da08e94f 100644
--- a/docshell/base/nsDocShell.cpp
+++ b/docshell/base/nsDocShell.cpp
@@ -10493,6 +10493,9 @@ nsDocShell::InternalLoad(nsIURI* aURI,
     (aFlags & INTERNAL_LOAD_FLAGS_ALLOW_THIRD_PARTY_FIXUP) != 0;
   mURIResultedInDocument = false;  // reset the clock...
 
+  // Note that there is code that relies on this check to stop us entering the
+  // `doShortCircuitedLoad` block below for certain load types.  (For example,
+  // reftest-content.js uses LOAD_FLAGS_BYPASS_CACHE for this purpose.)
   if (aLoadType == LOAD_NORMAL ||
       aLoadType == LOAD_STOP_CONTENT ||
       LOAD_TYPE_HAS_FLAGS(aLoadType, LOAD_FLAGS_REPLACE_HISTORY) ||
diff --git a/layout/tools/reftest/reftest-content.js b/layout/tools/reftest/reftest-content.js
index b357629d6b51..edcebd4adec9 100644
--- a/layout/tools/reftest/reftest-content.js
+++ b/layout/tools/reftest/reftest-content.js
@@ -1055,9 +1055,35 @@ function DoAssertionCheck()
     SendAssertionCount(numAsserts);
 }
 
+function URIsEqualIgnoringHash(uri1, uri2)
+{
+    let hashIndex1 = uri1.indexOf("#");
+    if (hashIndex1 > -1) {
+        uri1 = uri1.substr(0, hashIndex1);
+    }
+    let hashIndex2 = uri2.indexOf("#");
+    if (hashIndex2 > -1) {
+        uri2 = uri2.substr(0, hashIndex2);
+    }
+    return uri1 == uri2;
+}
+
 function LoadURI(uri)
 {
-    var flags = webNavigation().LOAD_FLAGS_NONE;
+    let flags = CI.nsIWebNavigation.LOAD_FLAGS_NONE;
+
+    if (URIsEqualIgnoringHash(uri, gCurrentURL)) {
+        // In this case the new URI would normally just cause an anchor scroll
+        // so we use LOAD_FLAGS_BYPASS_CACHE to force a reload so we'll get a
+        // 'load' event.  (The code that handles new URIs once they're ready is
+        // triggered by a 'load' event, so we'll time out if we don't get one).
+        //
+        // Note that we avoid using this flag in general since we don't want
+        // to unnecessarily reload and reprocess common font files, images,
+        // etc. for every test/reference (that may slow down reftest runs).
+        flags = CI.nsIWebNavigation.LOAD_FLAGS_BYPASS_CACHE;
+    }
+
     webNavigation().loadURI(uri, flags, null, null, null);
 }