--- a/dom/base/Element.cpp
+++ b/dom/base/Element.cpp
@@ -1881,33 +1881,33 @@ Element::UnbindFromTree(bool aDeep, bool
                    presContext->GetViewportScrollbarStylesOverrideNode(),
                    "Leaving behind a raw pointer to this node (as having "
                    "propagated scrollbar styles) - that's dangerous...");
       }
     }
   }
 #endif
 
+  ClearInDocument();
+
   // Ensure that CSS transitions don't continue on an element at a
   // different place in the tree (even if reinserted before next
   // animation refresh).
   // We need to delete the properties while we're still in document
   // (if we were in document).
   // FIXME (Bug 522599): Need a test for this.
   if (MayHaveAnimations()) {
     DeleteProperty(nsGkAtoms::transitionsOfBeforeProperty);
     DeleteProperty(nsGkAtoms::transitionsOfAfterProperty);
     DeleteProperty(nsGkAtoms::transitionsProperty);
     DeleteProperty(nsGkAtoms::animationsOfBeforeProperty);
     DeleteProperty(nsGkAtoms::animationsOfAfterProperty);
     DeleteProperty(nsGkAtoms::animationsProperty);
   }
 
-  ClearInDocument();
-
   // Computed style data isn't useful for detached nodes, and we'll need to
   // recompute it anyway if we ever insert the nodes back into a document.
   if (IsStyledByServo()) {
     if (document) {
       ClearServoData(document);
     } else {
       MOZ_ASSERT(!HasServoData());
       MOZ_ASSERT(!HasAnyOfFlags(kAllServoDescendantBits | NODE_NEEDS_FRAME));

new file mode 100644
--- /dev/null
+++ b/layout/style/crashtests/1396041.html
@@ -0,0 +1,9 @@
+<script>
+document.documentElement.appendChild(document.createElement("meter"))
+a = document.createElement("textarea")
+document.documentElement.appendChild(a)
+b = document.createElement("style")
+b.appendChild(document.createTextNode("*::-moz-meter-bar { text-indent: calc(50%); scroll-behavior: smooth; transition-duration: 250ms; }"))
+a.select()
+document.head.appendChild(b)
+</script>

--- a/layout/style/crashtests/crashtests.list
+++ b/layout/style/crashtests/crashtests.list
@@ -206,8 +206,9 @@ load 1388234.html
 load 1391577.html
 load 1393189.html
 load 1393580.html
 load 1389645.html
 load 1390726.html
 load 1393791.html
 load 1384232.html
 load 1395725.html
+load 1396041.html