--- a/layout/base/nsLayoutUtils.cpp
+++ b/layout/base/nsLayoutUtils.cpp
@@ -3168,33 +3168,32 @@ nsLayoutUtils::GetFramesForArea(nsIFrame
     if (rootScrollFrame) {
       builder.SetIgnoreScrollFrame(rootScrollFrame);
     }
   }
   if (aFlags & IGNORE_CROSS_DOC) {
     builder.SetDescendIntoSubdocuments(false);
   }
 
-  builder.SetHitTestShouldStopAtFirstOpaque(aFlags & ONLY_VISIBLE);
-
   builder.EnterPresShell(aFrame);
   aFrame->BuildDisplayListForStackingContext(&builder, aRect, &list);
   builder.LeavePresShell(aFrame, nullptr);
 
 #ifdef MOZ_DUMP_PAINTING
   if (gDumpEventList) {
     fprintf_stderr(stderr, "Event handling --- (%d,%d):\n", aRect.x, aRect.y);
 
     std::stringstream ss;
     nsFrame::PrintDisplayList(&builder, list, ss);
     print_stderr(ss);
   }
 #endif
 
   nsDisplayItem::HitTestState hitTestState;
+  builder.SetHitTestShouldStopAtFirstOpaque(aFlags & ONLY_VISIBLE);
   list.HitTest(&builder, aRect, &hitTestState, &aOutFrames);
   list.DeleteAll();
   return NS_OK;
 }
 
 // aScrollFrameAsScrollable must be non-nullptr and queryable to an nsIFrame
 FrameMetrics
 nsLayoutUtils::CalculateBasicFrameMetrics(nsIScrollableFrame* aScrollFrame) {

--- a/layout/base/nsLayoutUtils.h
+++ b/layout/base/nsLayoutUtils.h
@@ -820,17 +820,17 @@ public:
   static nsIFrame* GetFrameForPoint(nsIFrame* aFrame, nsPoint aPt,
                                     uint32_t aFlags = 0);
 
   /**
    * Given aFrame, the root frame of a stacking context, find all descendant
    * frames under the area of a rectangle that receives a mouse event,
    * or nullptr if there is no such frame.
    * @param aRect the rect, relative to the frame origin
-   * @param aOutFrames an array to append all the frames found
+   * @param aOutFrames an array to add all the frames found
    * @param aFlags some combination of FrameForPointFlags
    */
   static nsresult GetFramesForArea(nsIFrame* aFrame, const nsRect& aRect,
                                    nsTArray<nsIFrame*> &aOutFrames,
                                    uint32_t aFlags = 0);
 
   /**
    * Transform aRect relative to aFrame up to the coordinate system of

--- a/layout/forms/nsHTMLButtonControlFrame.cpp
+++ b/layout/forms/nsHTMLButtonControlFrame.cpp
@@ -114,17 +114,17 @@ nsHTMLButtonControlFrame::BuildDisplayLi
   nsDisplayList onTop;
   if (IsVisibleForPainting(aBuilder)) {
     mRenderer.DisplayButton(aBuilder, aLists.BorderBackground(), &onTop);
   }
 
   nsDisplayListCollection set;
 
   // Do not allow the child subtree to receive events.
-  if (!isForEventDelivery || aBuilder->HitTestShouldStopAtFirstOpaque()) {
+  if (!isForEventDelivery) {
     DisplayListClipState::AutoSaveRestore clipState(aBuilder);
 
     if (ShouldClipPaintingToBorderBox()) {
       nsMargin border = StyleBorder()->GetComputedBorder();
       nsRect rect(aBuilder->ToReferenceFrame(this), GetSize());
       rect.Deflate(border);
       nscoord radii[8];
       bool hasRadii = GetPaddingBoxBorderRadii(radii);

--- a/toolkit/components/typeaheadfind/nsITypeAheadFind.idl
+++ b/toolkit/components/typeaheadfind/nsITypeAheadFind.idl
@@ -13,17 +13,17 @@
 /******************************** Declarations *******************************/
 
 interface mozIDOMWindow;
 interface nsIDocShell;
 
 
 /****************************** nsTypeAheadFind ******************************/
 
-[scriptable, uuid(3cfe7906-f189-45a0-8abe-8e4437a23cae)]
+[scriptable, uuid(ae501e28-c57f-4692-ac74-410e1bed98b7)]
 interface nsITypeAheadFind : nsISupports
 {
   /****************************** Initializer ******************************/
 
   /* Necessary initialization that can't happen in the constructor, either
    * because function calls here may fail, or because the docShell is
    * required. */
   void init(in nsIDocShell aDocShell);
@@ -53,17 +53,17 @@ interface nsITypeAheadFind : nsISupports
   void setSelectionModeAndRepaint(in short toggle);
 
   /* Collapse the "found match" selection to its start.  Because not all
    * matches are owned by the same selection controller, this doesn't
    * necessarily happen automatically. */
   void collapseSelection();
 
   /* Check if a range is visible */
-  boolean isRangeVisible(in nsIDOMRange aRange, in boolean aFlushLayout);
+  boolean isRangeVisible(in nsIDOMRange aRange, in boolean aMustBeInViewPort);
 
   /******************************* Attributes ******************************/
 
   readonly attribute AString searchString;
                                         // Most recent search string
   attribute boolean caseSensitive;      // Searches are case sensitive
   attribute boolean entireWord;         // Search for whole words only
   readonly attribute nsIDOMElement foundLink;

--- a/toolkit/components/typeaheadfind/nsTypeAheadFind.cpp
+++ b/toolkit/components/typeaheadfind/nsTypeAheadFind.cpp
@@ -47,17 +47,16 @@
 #include "nsNameSpaceManager.h"
 #include "nsIWindowWatcher.h"
 #include "nsIObserverService.h"
 #include "nsFocusManager.h"
 #include "mozilla/dom/Element.h"
 #include "mozilla/dom/Link.h"
 #include "nsRange.h"
 #include "nsXBLBinding.h"
-#include "nsLayoutUtils.h"
 
 #include "nsTypeAheadFind.h"
 
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(nsTypeAheadFind)
   NS_INTERFACE_MAP_ENTRY(nsITypeAheadFind)
   NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsITypeAheadFind)
   NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
   NS_INTERFACE_MAP_ENTRY(nsIObserver)
@@ -66,16 +65,18 @@ NS_INTERFACE_MAP_END
 NS_IMPL_CYCLE_COLLECTING_ADDREF(nsTypeAheadFind)
 NS_IMPL_CYCLE_COLLECTING_RELEASE(nsTypeAheadFind)
 
 NS_IMPL_CYCLE_COLLECTION(nsTypeAheadFind, mFoundLink, mFoundEditable,
                          mCurrentWindow, mStartFindRange, mSearchRange,
                          mStartPointRange, mEndPointRange, mSoundInterface,
                          mFind, mFoundRange)
 
+static NS_DEFINE_CID(kFrameTraversalCID, NS_FRAMETRAVERSAL_CID);
+
 #define NS_FIND_CONTRACTID "@mozilla.org/embedcomp/rangefind;1"
 
 nsTypeAheadFind::nsTypeAheadFind():
   mStartLinksOnlyPref(false),
   mCaretBrowsingOn(false),
   mDidAddObservers(false),
   mLastFindLength(0),
   mIsSoundInitialized(false),
@@ -416,31 +417,32 @@ nsTypeAheadFind::FindItNow(nsIPresShell 
     return NS_ERROR_FAILURE;
 
   mFind->SetFindBackwards(aFindPrev);
 
   while (true) {    // ----- Outer while loop: go through all docs -----
     while (true) {  // === Inner while loop: go through a single doc ===
       mFind->Find(mTypeAheadBuffer.get(), mSearchRange, mStartPointRange,
                   mEndPointRange, getter_AddRefs(returnRange));
-
+      
       if (!returnRange)
         break;  // Nothing found in this doc, go to outer loop (try next doc)
 
       // ------- Test resulting found range for success conditions ------
       bool isInsideLink = false, isStartingLink = false;
 
       if (aIsLinksOnly) {
         // Don't check if inside link when searching all text
         RangeStartsInsideLink(returnRange, presShell, &isInsideLink,
                               &isStartingLink);
       }
 
       bool usesIndependentSelection;
-      if (!IsRangeVisible(presShell, presContext, returnRange, true,
+      if (!IsRangeVisible(presShell, presContext, returnRange,
+                          aIsFirstVisiblePreferred, false,
                           getter_AddRefs(mStartPointRange), 
                           &usesIndependentSelection) ||
           (aIsLinksOnly && !isInsideLink) ||
           (mStartLinksOnlyPref && aIsLinksOnly && !isStartingLink)) {
         // ------ Failure ------
         // At this point mStartPointRange got updated to the first
         // visible range in the viewport.  We _may_ be able to just
         // start there, if it's not taking us in the wrong direction.
@@ -810,17 +812,18 @@ nsTypeAheadFind::GetSearchContainers(nsI
     if (selection)
       selection->GetRangeAt(0, getter_AddRefs(currentSelectionRange));
   }
 
   if (!currentSelectionRange) {
     // Ensure visible range, move forward if necessary
     // This uses ignores the return value, but usese the side effect of
     // IsRangeVisible. It returns the first visible range after searchRange
-    IsRangeVisible(presShell, presContext, mSearchRange, true,
+    IsRangeVisible(presShell, presContext, mSearchRange, 
+                   aIsFirstVisiblePreferred, true, 
                    getter_AddRefs(mStartPointRange), nullptr);
   }
   else {
     int32_t startOffset;
     nsCOMPtr<nsIDOMNode> startNode;
     if (aFindPrev) {
       currentSelectionRange->GetStartContainer(getter_AddRefs(startNode));
       currentSelectionRange->GetStartOffset(&startOffset);
@@ -1000,28 +1003,28 @@ nsTypeAheadFind::Find(const nsAString& a
     // is typed
     mStartFindRange = nullptr;
     mSelectionController = nullptr;
 
     *aResult = FIND_FOUND;
     return NS_OK;
   }
 
-  bool atEnd = false;
+  bool atEnd = false;    
   if (mTypeAheadBuffer.Length()) {
     const nsAString& oldStr = Substring(mTypeAheadBuffer, 0, mTypeAheadBuffer.Length());
     const nsAString& newStr = Substring(aSearchString, 0, mTypeAheadBuffer.Length());
     if (oldStr.Equals(newStr))
       atEnd = true;
-
+  
     const nsAString& newStr2 = Substring(aSearchString, 0, aSearchString.Length());
     const nsAString& oldStr2 = Substring(mTypeAheadBuffer, 0, aSearchString.Length());
     if (oldStr2.Equals(newStr2))
       atEnd = true;
-
+    
     if (!atEnd)
       mStartFindRange = nullptr;
   }
 
   if (!mIsSoundInitialized && !mNotFoundSoundURL.IsEmpty()) {
     // This makes sure system sound library is loaded so that
     // there's no lag before the first sound is played
     // by waiting for the first keystroke, we still get the startup time benefits.
@@ -1153,122 +1156,160 @@ nsTypeAheadFind::GetFoundRange(nsIDOMRan
   }
 
   mFoundRange->CloneRange(aFoundRange);
   return NS_OK;
 }
 
 NS_IMETHODIMP
 nsTypeAheadFind::IsRangeVisible(nsIDOMRange *aRange,
-                                bool aFlushLayout,
+                                bool aMustBeInViewPort,
                                 bool *aResult)
 {
   // Jump through hoops to extract the docShell from the range.
   nsCOMPtr<nsIDOMNode> node;
   aRange->GetStartContainer(getter_AddRefs(node));
   nsCOMPtr<nsIDOMDocument> document;
   node->GetOwnerDocument(getter_AddRefs(document));
   nsCOMPtr<mozIDOMWindowProxy> window;
   document->GetDefaultView(getter_AddRefs(window));
   nsCOMPtr<nsIWebNavigation> navNav (do_GetInterface(window));
   nsCOMPtr<nsIDocShell> docShell (do_GetInterface(navNav));
 
   // Set up the arguments needed to check if a range is visible.
   nsCOMPtr<nsIPresShell> presShell (docShell->GetPresShell());
   RefPtr<nsPresContext> presContext = presShell->GetPresContext();
   nsCOMPtr<nsIDOMRange> startPointRange = new nsRange(presShell->GetDocument());
-  *aResult = IsRangeVisible(presShell, presContext, aRange, aFlushLayout,
+  *aResult = IsRangeVisible(presShell, presContext, aRange,
+                            aMustBeInViewPort, false,
                             getter_AddRefs(startPointRange),
                             nullptr);
   return NS_OK;
 }
 
 bool
 nsTypeAheadFind::IsRangeVisible(nsIPresShell *aPresShell,
                                 nsPresContext *aPresContext,
-                                nsIDOMRange *aRange,
-                                bool aFlushLayout,
+                                nsIDOMRange *aRange, bool aMustBeInViewPort,
+                                bool aGetTopVisibleLeaf,
                                 nsIDOMRange **aFirstVisibleRange,
                                 bool *aUsesIndependentSelection)
 {
   NS_ASSERTION(aPresShell && aPresContext && aRange && aFirstVisibleRange, 
                "params are invalid");
 
-  // We need to know if the range start and end are both visible.
-  // In all cases, return the first visible range in aFirstVisibleRange.
-  aRange->CloneRange(aFirstVisibleRange);
+  // We need to know if the range start is visible.
+  // Otherwise, return the first visible range start 
+  // in aFirstVisibleRange
 
-  if (aFlushLayout) {
-    aPresShell->FlushPendingNotifications(Flush_Layout);
-  }
-
+  aRange->CloneRange(aFirstVisibleRange);
   nsCOMPtr<nsIDOMNode> node;
-  aRange->GetCommonAncestorContainer(getter_AddRefs(node));
+  aRange->GetStartContainer(getter_AddRefs(node));
 
   nsCOMPtr<nsIContent> content(do_QueryInterface(node));
-  if (!content) {
+  if (!content)
     return false;
-  }
 
   nsIFrame *frame = content->GetPrimaryFrame();
-  if (!frame) {
+  if (!frame)    
     return false;  // No frame! Not visible then.
-  }
-
-  // Having a primary frame doesn't mean that the range is visible inside the
-  // viewport. Do a hit-test to determine that quickly and properly.
-  bool foundContent = false;
-  AutoTArray<nsIFrame*,8> frames;
-  nsIFrame *rootFrame = aPresShell->GetRootFrame();
-  RefPtr<nsRange> range = static_cast<nsRange*>(aRange);
-  RefPtr<mozilla::dom::DOMRectList> rects = range->GetClientRects(true, false);
-  for (uint32_t i = 0; i < rects->Length(); ++i) {
-    RefPtr<mozilla::dom::DOMRect> rect = rects->Item(i);
-    nsRect r(nsPresContext::CSSPixelsToAppUnits((float)rect->X()),
-             nsPresContext::CSSPixelsToAppUnits((float)rect->Y()),
-             nsPresContext::CSSPixelsToAppUnits((float)rect->Width()),
-             nsPresContext::CSSPixelsToAppUnits((float)rect->Height()));
-    // Append visible frames to frames array.
-    nsLayoutUtils::GetFramesForArea(rootFrame, r, frames,
-      nsLayoutUtils::IGNORE_PAINT_SUPPRESSION |
-      nsLayoutUtils::IGNORE_ROOT_SCROLL_FRAME |
-      nsLayoutUtils::ONLY_VISIBLE);
 
-    // See if any of the frames contain the content. If they do, then the range
-    // is visible. We search for the content rather than the original frame,
-    // because nsTextContinuation frames might be returned instead of the
-    // original frame.
-    for (const auto &f: frames) {
-      if (f->GetContent() == content) {
-        foundContent = true;
-        break;
-      }
-    }
-
-    if (foundContent) {
-      break;
-    }
-
-    frames.ClearAndRetainStorage();
-  }
-
-  // Test that content appears in the list of framesForArea. If it does, then
-  // that means that content is at least partly visible.
-  if (!foundContent) {
+  if (!frame->StyleVisibility()->IsVisible())
     return false;
-  }
 
   // Detect if we are _inside_ a text control, or something else with its own
   // selection controller.
   if (aUsesIndependentSelection) {
     *aUsesIndependentSelection = 
       (frame->GetStateBits() & NS_FRAME_INDEPENDENT_SELECTION);
   }
 
-  return true;
+  // ---- We have a frame ----
+  if (!aMustBeInViewPort)   
+    return true; //  Don't need it to be on screen, just in rendering tree
+
+  // Get the next in flow frame that contains the range start
+  int32_t startRangeOffset, startFrameOffset, endFrameOffset;
+  aRange->GetStartOffset(&startRangeOffset);
+  while (true) {
+    frame->GetOffsets(startFrameOffset, endFrameOffset);
+    if (startRangeOffset < endFrameOffset)
+      break;
+
+    nsIFrame *nextContinuationFrame = frame->GetNextContinuation();
+    if (nextContinuationFrame)
+      frame = nextContinuationFrame;
+    else
+      break;
+  }
+
+  // Set up the variables we need, return true if we can't get at them all
+  const uint16_t kMinPixels  = 12;
+  nscoord minDistance = nsPresContext::CSSPixelsToAppUnits(kMinPixels);
+
+  // Get the bounds of the current frame, relative to the current view.
+  // We don't use the more accurate AccGetBounds, because that is
+  // more expensive and the STATE_OFFSCREEN flag that this is used
+  // for only needs to be a rough indicator
+  nsRectVisibility rectVisibility = nsRectVisibility_kAboveViewport;
+
+  if (!aGetTopVisibleLeaf && !frame->GetRect().IsEmpty()) {
+    rectVisibility =
+      aPresShell->GetRectVisibility(frame,
+                                    nsRect(nsPoint(0,0), frame->GetSize()),
+                                    minDistance);
+
+    if (rectVisibility != nsRectVisibility_kAboveViewport) {
+      return true;
+    }
+  }
+
+  // We know that the target range isn't usable because it's not in the
+  // view port. Move range forward to first visible point,
+  // this speeds us up a lot in long documents
+  nsCOMPtr<nsIFrameEnumerator> frameTraversal;
+  nsCOMPtr<nsIFrameTraversal> trav(do_CreateInstance(kFrameTraversalCID));
+  if (trav)
+    trav->NewFrameTraversal(getter_AddRefs(frameTraversal),
+                            aPresContext, frame,
+                            eLeaf,
+                            false, // aVisual
+                            false, // aLockInScrollView
+                            false, // aFollowOOFs
+                            false  // aSkipPopupChecks
+                            );
+
+  if (!frameTraversal)
+    return false;
+
+  while (rectVisibility == nsRectVisibility_kAboveViewport) {
+    frameTraversal->Next();
+    frame = frameTraversal->CurrentItem();
+    if (!frame)
+      return false;
+
+    if (!frame->GetRect().IsEmpty()) {
+      rectVisibility =
+        aPresShell->GetRectVisibility(frame,
+                                      nsRect(nsPoint(0,0), frame->GetSize()),
+                                      minDistance);
+    }
+  }
+
+  if (frame) {
+    nsCOMPtr<nsIDOMNode> firstVisibleNode = do_QueryInterface(frame->GetContent());
+
+    if (firstVisibleNode) {
+      frame->GetOffsets(startFrameOffset, endFrameOffset);
+      (*aFirstVisibleRange)->SetStart(firstVisibleNode, startFrameOffset);
+      (*aFirstVisibleRange)->SetEnd(firstVisibleNode, endFrameOffset);
+    }
+  }
+
+  return false;
 }
 
 already_AddRefed<nsIPresShell>
 nsTypeAheadFind::GetPresShell()
 {
   if (!mPresShell)
     return nullptr;
 

--- a/toolkit/components/typeaheadfind/nsTypeAheadFind.h
+++ b/toolkit/components/typeaheadfind/nsTypeAheadFind.h
@@ -51,18 +51,18 @@ protected:
   void RangeStartsInsideLink(nsIDOMRange *aRange, nsIPresShell *aPresShell, 
                              bool *aIsInsideLink, bool *aIsStartingLink);
 
   void GetSelection(nsIPresShell *aPresShell, nsISelectionController **aSelCon, 
                     nsISelection **aDomSel);
   // *aNewRange may not be collapsed.  If you want to collapse it in a
   // particular way, you need to do it yourself.
   bool IsRangeVisible(nsIPresShell *aPresShell, nsPresContext *aPresContext,
-                        nsIDOMRange *aRange, bool aFlushLayout,
-                        nsIDOMRange **aNewRange,
+                        nsIDOMRange *aRange, bool aMustBeVisible, 
+                        bool aGetTopVisibleLeaf, nsIDOMRange **aNewRange,
                         bool *aUsesIndependentSelection);
   nsresult FindItNow(nsIPresShell *aPresShell, bool aIsLinksOnly,
                      bool aIsFirstVisiblePreferred, bool aFindPrev,
                      uint16_t* aResult);
   nsresult GetSearchContainers(nsISupports *aContainer,
                                nsISelectionController *aSelectionController,
                                bool aIsFirstVisiblePreferred,
                                bool aFindPrev, nsIPresShell **aPresShell,
@@ -90,17 +90,17 @@ protected:
   // mLastFindLength is the character length of the last find string.  It is used for
   // disabling the "not found" sound when using backspace or delete
   uint32_t mLastFindLength;
 
   // Sound is played asynchronously on some platforms.
   // If we destroy mSoundInterface before sound has played, it won't play
   nsCOMPtr<nsISound> mSoundInterface;
   bool mIsSoundInitialized;
-
+  
   // where selection was when user started the find
   nsCOMPtr<nsIDOMRange> mStartFindRange;
   nsCOMPtr<nsIDOMRange> mSearchRange;
   nsCOMPtr<nsIDOMRange> mStartPointRange;
   nsCOMPtr<nsIDOMRange> mEndPointRange;
 
   // Cached useful interfaces
   nsCOMPtr<nsIFind> mFind;

--- a/toolkit/modules/FinderHighlighter.jsm
+++ b/toolkit/modules/FinderHighlighter.jsm
@@ -1132,19 +1132,16 @@ FinderHighlighter.prototype = {
     this._updateRangeOutline(dict);
 
     let allRects = [];
     if (paintContent || dict.modalHighlightAllMask) {
       this._updateDynamicRangesRects(dict);
 
       let DOMRect = window.DOMRect;
       for (let [range, rectsAndTexts] of dict.modalHighlightRectsMap) {
-        if (!this.finder._fastFind.isRangeVisible(range, false))
-          continue;
-
         if (dict.updateAllRanges)
           rectsAndTexts = this._updateRangeRects(range);
 
         // If a geometry change was detected, we bail out right away here, because
         // the current set of ranges has been invalidated.
         if (dict.detectedGeometryChange)
           return;
 

--- a/toolkit/modules/FinderIterator.jsm
+++ b/toolkit/modules/FinderIterator.jsm
@@ -562,17 +562,23 @@ this.FinderIterator = {
       return frames;
 
     // Casting `window.frames` to an Iterator doesn't work, so we're stuck with
     // a plain, old for-loop.
     for (let i = 0, l = window.frames.length; i < l; ++i) {
       let frame = window.frames[i];
       // Don't count matches in hidden frames.
       let frameEl = frame && frame.frameElement;
-      if (!frameEl || !frameEl.getClientRects().length)
+      if (!frameEl)
+        continue;
+      // Construct a range around the frame element to check its visiblity.
+      let range = window.document.createRange();
+      range.setStart(frameEl, 0);
+      range.setEnd(frameEl, 0);
+      if (!finder._fastFind.isRangeVisible(range, this._getDocShell(range), true))
         continue;
       // All conditions pass, so push the current frame and its children on the
       // stack.
       frames.push(frame, ...this._collectFrames(frame, finder));
     }
 
     return frames;
   },