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src/lib/annotations/annotations.html

@@ -369,10 +369,13 @@
         if (node.localName === 'input' && origName === 'value') {
           node.setAttribute(origName, '');
         }
-        // Remove annotation
+        // Support `disable-upgrade` feature by maintaining this
+        // attribute so that it can be found on an element at
+        // `createdCallback` time.
         if (disableUpgradeEnabled && origName === 'disable-upgrade$') {
           node.setAttribute(name, '');
         }
+        // Remove annotation
         node.removeAttribute(origName);
         // Case hackery: attributes are lower-case, but bind targets
         // (properties) are case sensitive. Gambit is to map dash-case to