Checks for existing scrollTarget before overwriting

Fixes PolymerElements#547
bennypowers · Apr 23, 2018 · 65ea99c · 65ea99c
1 parent e62995a
commit 65ea99c
Showing 1 changed file with 4 additions and 3 deletions.
diff --git a/app-header-layout/app-header-layout.html b/app-header-layout/app-header-layout.html
@@ -178,9 +178,10 @@
         // the content until the height of the header can be read.
         this.$.wrapper.classList.remove('initializing');
         // Update scroll target.
-        header.scrollTarget = this.hasScrollingRegion ?
-            this.$.contentContainer :
-            this.ownerDocument.documentElement;
+        header.scrollTarget =
+            !header.scrollTarget === header._defaultScrollTarget ? header.scrollTarget
+          : this.hasScrollingRegion ? this.$.contentContainer
+          : this.ownerDocument.documentElement;
         // Get header height here so that style reads are batched together before
         // style writes (i.e. getBoundingClientRect() below).
         var headerHeight = header.offsetHeight;