diff --git a/devtools/server/actors/inspector/walker.js b/devtools/server/actors/inspector/walker.js
index 4821d191c7c4..4549e42c4cd7 100644
--- a/devtools/server/actors/inspector/walker.js
+++ b/devtools/server/actors/inspector/walker.js
@@ -521,10 +521,18 @@ var WalkerActor = protocol.ActorClassWithSpec(walkerSpec, {
     // - more than one child
     // - unique child is not a text node
     // - unique child is a text node, but is too long to be inlined
+    // - we are a slot -> these are always represented on their own lines with
+    //                    a link to the original node.
+    const isAssignedSlot =
+      !!firstChild &&
+      node.rawNode.nodeName === "SLOT" &&
+      isDirectShadowHostChild(firstChild);
+
     if (!firstChild ||
         walker.nextSibling() ||
         firstChild.nodeType !== Node.TEXT_NODE ||
-        firstChild.nodeValue.length > gValueSummaryLength
+        firstChild.nodeValue.length > gValueSummaryLength ||
+        isAssignedSlot
         ) {
       return undefined;
     }
diff --git a/devtools/server/tests/browser/browser_inspector-shadow.js b/devtools/server/tests/browser/browser_inspector-shadow.js
index 8675b3b14d7f..c374732ad894 100644
--- a/devtools/server/tests/browser/browser_inspector-shadow.js
+++ b/devtools/server/tests/browser/browser_inspector-shadow.js
@@ -115,3 +115,25 @@ add_task(async function() {
   is(closedShadowRoot.shadowRootMode, "closed",
     "#mode-closed has a shadow root with closed mode");
 });
+
+add_task(async function() {
+  info("Test that slotted inline text nodes appear in the Shadow DOM tree");
+  const { walker } = await initInspectorFront(URL);
+
+  const el = await walker.querySelector(walker.rootNode, "#slot-inline-text");
+  const hostChildren = await walker.children(el);
+  const originalSlot = hostChildren.nodes[1];
+  is(originalSlot.displayName, "#text", "Shadow host as a text node to be slotted");
+
+  const shadowRoot = hostChildren.nodes[0];
+  const shadowChildren = await walker.children(shadowRoot);
+  const slot = shadowChildren.nodes[0];
+  is(slot.displayName, "slot", "shadow-root has a slot child");
+  ok(!slot._form.inlineTextChild, "Slotted node is not an inline text");
+
+  const slotChildren = await walker.children(slot);
+  const slotted = slotChildren.nodes[0];
+  is(slotted.displayName, "#text", "Slotted node is a text node");
+  is(slotted._form.nodeValue, originalSlot._form.nodeValue,
+    "Slotted content is the same as original's");
+});
diff --git a/devtools/server/tests/browser/inspector-shadow.html b/devtools/server/tests/browser/inspector-shadow.html
index 6da30689b143..5d6fa37e5bf9 100644
--- a/devtools/server/tests/browser/inspector-shadow.html
+++ b/devtools/server/tests/browser/inspector-shadow.html
@@ -53,6 +53,14 @@
         <slot></slot>`;
       }
     });
+
+    customElements.define("test-simple-slot", class extends HTMLElement {
+      constructor() {
+        super();
+        this.attachShadow({ mode: "open"});
+        this.shadowRoot.innerHTML = "<slot></slot>";
+      }
+    });
   };
   </script>
   <style>
@@ -93,5 +101,11 @@
 
   <test-empty id="mode-open"></test-empty>
   <test-empty-closed id="mode-closed"></test-empty-closed>
+
+  <hr>
+
+  <test-simple-slot id="slot-inline-text">
+    Lorem ipsum
+  </test-simple-slot>
 </body>
 </html>
diff --git a/gfx/webrender_bindings/Moz2DImageRenderer.cpp b/gfx/webrender_bindings/Moz2DImageRenderer.cpp
index b6e0cb00ff0a..53308d506ae2 100644
--- a/gfx/webrender_bindings/Moz2DImageRenderer.cpp
+++ b/gfx/webrender_bindings/Moz2DImageRenderer.cpp
@@ -410,12 +410,14 @@ static bool Moz2DRenderCallback(const Range<const uint8_t> aBlob,
 
   };
 
-  MOZ_RELEASE_ASSERT(aBlob.length() > sizeof(size_t));
+  // We try hard to not have empty blobs but we can end up with
+  // them because of CompositorHitTestInfo and merging.
+  MOZ_RELEASE_ASSERT(aBlob.length() >= sizeof(size_t));
   size_t indexOffset = *(size_t*)(aBlob.end().get()-sizeof(size_t));
   MOZ_RELEASE_ASSERT(indexOffset + sizeof(size_t) <= aBlob.length());
   Reader reader(aBlob.begin().get()+indexOffset, aBlob.length()-sizeof(size_t)-indexOffset);
 
-  bool ret;
+  bool ret = true;
   size_t offset = 0;
   auto absBounds = IntRectAbsolute::FromRect(bounds);
   while (reader.pos < reader.len) {
diff --git a/intl/l10n/DocumentL10n.cpp b/intl/l10n/DocumentL10n.cpp
index 5c6ecd70776e..28b01d24f8a2 100644
--- a/intl/l10n/DocumentL10n.cpp
+++ b/intl/l10n/DocumentL10n.cpp
@@ -65,6 +65,12 @@ DocumentL10n::Init(nsTArray<nsString>& aResourceIds)
   // is ready for localization.
   uint32_t ret;
   mDOMLocalization->AddResourceIds(aResourceIds, true, &ret);
+
+  // Register observers for this instance of
+  // mozDOMLocalization to allow it to retranslate
+  // the document when locale changes or pseudolocalization
+  // gets turned on.
+  mDOMLocalization->RegisterObservers();
   return true;
 }
 
diff --git a/intl/l10n/mozIDOMLocalization.idl b/intl/l10n/mozIDOMLocalization.idl
index 59c0b0072574..2d87668f5301 100644
--- a/intl/l10n/mozIDOMLocalization.idl
+++ b/intl/l10n/mozIDOMLocalization.idl
@@ -14,6 +14,7 @@ interface mozIDOMLocalization : nsISupports
 {
   unsigned long addResourceIds(in Array<AString> resourceIds, in bool aEager);
   unsigned long removeResourceIds(in Array<AString> resourceIds);
+  void registerObservers();
 
   Promise formatMessages(in Array<jsval> aKeys);
   Promise formatValues(in Array<jsval> aKeys);
diff --git a/intl/l10n/test/test_mozdomlocalization.js b/intl/l10n/test/test_mozdomlocalization.js
index 961e12f995a5..5c063558a291 100644
--- a/intl/l10n/test/test_mozdomlocalization.js
+++ b/intl/l10n/test/test_mozdomlocalization.js
@@ -27,6 +27,7 @@ L10nRegistry.registerSource(source);
 add_task(function test_methods_presence() {
   equal(typeof domLocalization.addResourceIds, "function");
   equal(typeof domLocalization.removeResourceIds, "function");
+  equal(typeof domLocalization.registerObservers, "function");
 
   equal(typeof domLocalization.formatMessages, "function");
   equal(typeof domLocalization.formatValues, "function");
diff --git a/layout/svg/crashtests/crashtests.list b/layout/svg/crashtests/crashtests.list
index 7762edc44160..bf520051d409 100644
--- a/layout/svg/crashtests/crashtests.list
+++ b/layout/svg/crashtests/crashtests.list
@@ -212,6 +212,7 @@ load 1467552-1.html
 load conditional-outer-svg-nondirty-reflow-assert.xhtml
 load extref-test-1.xhtml
 load blob-merging-and-retained-display-list.html
+load empty-blob-merging.html
 load grouping-empty-bounds.html
 load 1480275.html
 load 1480224.html
diff --git a/layout/svg/crashtests/empty-blob-merging.html b/layout/svg/crashtests/empty-blob-merging.html
new file mode 100644
index 000000000000..4b603c19d9b4
--- /dev/null
+++ b/layout/svg/crashtests/empty-blob-merging.html
@@ -0,0 +1,48 @@
+<html class="reftest-wait">
+<style>
+@keyframes spinnow {
+    100% {
+        transform: rotate(360deg) scale(.2, .2);
+    }
+}
+
+rect {
+    transform: rotate(0deg) scale(0.6, 1);
+    transform-origin: center;
+    animation: 5s spinnow infinite linear;
+}
+
+</style>
+<svg width=400 height=400>
+        <!--
+          onwheel is needed so that we get a hit test info display item
+          before the transform on the rect
+        -->
+	<g onwheel="alert(1)">
+	<g id="gr">
+	<circle r=30 fill=yellow cx=300 cy=100 />
+	<circle r=30 fill=yellow cx=10 cy=100 />
+	<circle r=30 fill=yellow cx=300 cy=300 />
+	<circle r=30 fill=yellow cx=10 cy=300 />
+	</g>
+	<rect width=100 height=100 fill=blue x=100 y=100 />
+	<g opacity=0.5>
+	<circle r=30 fill=pink cx=300 cy=100 />
+	<circle r=30 fill=pink cx=10 cy=100 />
+	<circle r=30 fill=pink cx=300 cy=300 />
+	<circle r=30 fill=pink cx=10 cy=300 />
+	</g>
+	</g>
+</svg>
+<script>
+  function blam() {
+    let gr = document.getElementById("gr");
+    gr.remove();
+    document.documentElement.removeAttribute("class");
+  }
+document.addEventListener("MozReftestInvalidate", function() {
+  requestAnimationFrame(function() {
+    blam();
+  });
+});
+</script>
diff --git a/toolkit/crashreporter/nsExceptionHandler.cpp b/toolkit/crashreporter/nsExceptionHandler.cpp
index 04b41edf4df0..06b7aa6deeda 100644
--- a/toolkit/crashreporter/nsExceptionHandler.cpp
+++ b/toolkit/crashreporter/nsExceptionHandler.cpp
@@ -1384,13 +1384,13 @@ ChildFPEFilter(void* context, EXCEPTION_POINTERS* exinfo,
 static MINIDUMP_TYPE
 GetMinidumpType()
 {
-  MINIDUMP_TYPE minidump_type = MiniDumpWithFullMemoryInfo;
+  MINIDUMP_TYPE minidump_type = static_cast<MINIDUMP_TYPE>(
+      MiniDumpWithFullMemoryInfo | MiniDumpWithUnloadedModules);
 
 #ifdef NIGHTLY_BUILD
   // This is Nightly only because this doubles the size of minidumps based
   // on the experimental data.
   minidump_type = static_cast<MINIDUMP_TYPE>(minidump_type |
-      MiniDumpWithUnloadedModules |
       MiniDumpWithProcessThreadData);
 
   // dbghelp.dll on Win7 can't handle overlapping memory regions so we only