Preserve watchElementForClose state across bfcache

CHANGELOG.md

@@ -2,6 +2,15 @@
 
 All notable changes to this project will be documented in this file. See [standard-version](https://github.com/conventional-changelog/standard-version) for commit guidelines.
 
+## [2.10.0-alpha.3](https://github.com/krakenjs/belter/compare/v2.9.3...v2.10.0-alpha.3) (2026-02-20)
+
+
+### Features
+
+* fix eslint errors ([5a8bde4](https://github.com/krakenjs/belter/commit/5a8bde47e156403d721ce9410724a2d62257da94))
+* update unload behvaior to support bfcache ([3443df8](https://github.com/krakenjs/belter/commit/3443df8360e1724557c1722418f404abbdf85fe9))
+* update version ([d528fcf](https://github.com/krakenjs/belter/commit/d528fcfab8df47ee0b01c52cce7cc24aae2dac06))
+
 ### [2.9.3](https://github.com/krakenjs/belter/compare/v2.9.2...v2.9.3) (2026-01-07)
 
 

dist/belter.js

@@ -2887,7 +2887,7 @@
                 cancelled = !0;
                 for (var _i16 = 0; _i16 < mutationObservers.length; _i16++) mutationObservers[_i16].disconnect();
                 interval && interval.cancel();
-                sacrificialFrameWin && sacrificialFrameWin.removeEventListener(terminationEvent, elementClosed);
+                sacrificialFrameWin && sacrificialFrameWin.removeEventListener(terminationEvent, elementClosedOnTermination);
                 sacrificialFrame && destroyElement(sacrificialFrame);
             };
             var elementClosed = function() {
@@ -2896,6 +2896,13 @@
                     cancel();
                 }
             };
+            var elementClosedOnTermination = function(event) {
+                console.log("[bfcache-belter] sacrificial iframe " + terminationEvent + " fired, persisted=" + event.persisted);
+                if ("pagehide" === terminationEvent && event.persisted) console.log("[bfcache-belter] skipping elementClosed (page entering bfcache)"); else {
+                    console.log("[bfcache-belter] calling elementClosed (real navigation)");
+                    elementClosed();
+                }
+            };
             if (isElementClosed(element)) {
                 elementClosed();
                 return {
@@ -2921,7 +2928,7 @@
                 (sacrificialFrameWin = function(win) {
                     if (!isSameDomain(win)) throw new Error("Expected window to be same domain");
                     return win;
-                }(frameWin)).addEventListener(terminationEvent, elementClosed);
+                }(frameWin)).addEventListener(terminationEvent, elementClosedOnTermination);
             }));
             element.appendChild(sacrificialFrame);
             interval = safeInterval((function() {

dist/module/dom.js

@@ -704,7 +704,7 @@ export function watchElementForClose(element, handler) {
       interval.cancel();
     }
     if (sacrificialFrameWin) {
-      sacrificialFrameWin.removeEventListener(terminationEvent, elementClosed);
+      sacrificialFrameWin.removeEventListener(terminationEvent, elementClosedOnTermination);
     }
     if (sacrificialFrame) {
       destroyElement(sacrificialFrame);
@@ -716,6 +716,15 @@ export function watchElementForClose(element, handler) {
       cancel();
     }
   };
+  var elementClosedOnTermination = function elementClosedOnTermination(event) {
+    console.log("[bfcache-belter] sacrificial iframe " + terminationEvent + " fired, persisted=" + event.persisted);
+    if (terminationEvent === "pagehide" && event.persisted) {
+      console.log("[bfcache-belter] skipping elementClosed (page entering bfcache)");
+      return;
+    }
+    console.log("[bfcache-belter] calling elementClosed (real navigation)");
+    elementClosed();
+  };
   if (isElementClosed(element)) {
     elementClosed();
     return {
@@ -742,7 +751,7 @@ export function watchElementForClose(element, handler) {
   sacrificialFrame.style.display = "none";
   awaitFrameWindow(sacrificialFrame).then(function (frameWin) {
     sacrificialFrameWin = assertSameDomain(frameWin);
-    sacrificialFrameWin.addEventListener(terminationEvent, elementClosed);
+    sacrificialFrameWin.addEventListener(terminationEvent, elementClosedOnTermination);
   });
   element.appendChild(sacrificialFrame);
   var check = function check() {

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@krakenjs/belter",
-  "version": "2.9.3",
+  "version": "2.10.0-alpha.3",
   "description": "Utilities.",
   "main": "index.js",
   "scripts": {

src/dom.js

@@ -1063,8 +1063,12 @@ export function watchElementForClose(
       interval.cancel();
     }
     if (sacrificialFrameWin) {
-      // eslint-disable-next-line no-use-before-define
-      sacrificialFrameWin.removeEventListener(terminationEvent, elementClosed);
+      /* eslint-disable no-use-before-define */
+      sacrificialFrameWin.removeEventListener(
+        terminationEvent,
+        elementClosedOnTermination
+      );
+      /* eslint-enable no-use-before-define */
     }
     if (sacrificialFrame) {
       destroyElement(sacrificialFrame);
@@ -1078,6 +1082,23 @@ export function watchElementForClose(
     }
   };
 
+  const elementClosedOnTermination = (event) => {
+    // eslint-disable-next-line no-console
+    console.log(
+      `[bfcache-belter] sacrificial iframe ${terminationEvent} fired, persisted=${event.persisted}`
+    );
+    if (terminationEvent === "pagehide" && event.persisted) {
+      // eslint-disable-next-line no-console
+      console.log(
+        "[bfcache-belter] skipping elementClosed (page entering bfcache)"
+      );
+      return;
+    }
+    // eslint-disable-next-line no-console
+    console.log("[bfcache-belter] calling elementClosed (real navigation)");
+    elementClosed();
+  };
+
   if (isElementClosed(element)) {
     elementClosed();
     return { cancel };
@@ -1107,7 +1128,10 @@ export function watchElementForClose(
   sacrificialFrame.style.display = "none";
   awaitFrameWindow(sacrificialFrame).then((frameWin) => {
     sacrificialFrameWin = assertSameDomain(frameWin);
-    sacrificialFrameWin.addEventListener(terminationEvent, elementClosed);
+    sacrificialFrameWin.addEventListener(
+      terminationEvent,
+      elementClosedOnTermination
+    );
   });
   element.appendChild(sacrificialFrame);