From 54d37638b42a50057c573b999050464e434fb980 Mon Sep 17 00:00:00 2001
From: batu_hoang <longvatrong111@gmail.com>
Date: Wed, 28 May 2025 18:03:52 +0800
Subject: [PATCH] Add flag for epoch mismatch

Signed-off-by: batu_hoang <longvatrong111@gmail.com>
---
 components/compositing/compositor.rs       | 4 ++++
 components/compositing/webview_renderer.rs | 7 +++++--
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/components/compositing/compositor.rs b/components/compositing/compositor.rs
index f63cb5ffae9..d174d54ae9c 100644
--- a/components/compositing/compositor.rs
+++ b/components/compositing/compositor.rs
@@ -814,10 +814,13 @@ impl IOCompositor {
                 let Some(webview_renderer) = self.webview_renderers.get_mut(webview_id) else {
                     return warn!("Could not find WebView for incoming display list");
                 };
+                webview_renderer.epoch_not_synchronized.set(true);
 
                 let pipeline_id = display_list_info.pipeline_id;
                 let details = webview_renderer.ensure_pipeline_details(pipeline_id.into());
+
                 details.most_recent_display_list_epoch = Some(display_list_info.epoch);
+
                 details.hit_test_items = display_list_info.hit_test_info;
                 details.install_new_scroll_tree(display_list_info.scroll_tree);
 
@@ -1662,6 +1665,7 @@ impl IOCompositor {
             // Process all pending events
             self.webview_renderers.iter().for_each(|webview| {
                 webview.dispatch_pending_input_events();
+                webview.epoch_not_synchronized.set(false);
             });
         }
 
diff --git a/components/compositing/webview_renderer.rs b/components/compositing/webview_renderer.rs
index d730a148e92..19535c7e785 100644
--- a/components/compositing/webview_renderer.rs
+++ b/components/compositing/webview_renderer.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-use std::cell::RefCell;
+use std::cell::{Cell, RefCell};
 use std::collections::hash_map::Keys;
 use std::collections::{HashMap, VecDeque};
 use std::rc::Rc;
@@ -100,6 +100,8 @@ pub(crate) struct WebViewRenderer {
     animating: bool,
     /// Pending input events queue. Priavte and only this thread pushes events to it.
     pending_input_events: RefCell<VecDeque<InputEvent>>,
+    /// Flag to indicate that the epoch has been not synchronized yet.
+    pub epoch_not_synchronized: Cell<bool>,
 }
 
 impl Drop for WebViewRenderer {
@@ -135,6 +137,7 @@ impl WebViewRenderer {
             hidpi_scale_factor: Scale::new(hidpi_scale_factor.0),
             animating: false,
             pending_input_events: Default::default(),
+            epoch_not_synchronized: Cell::default(),
         }
     }
 
@@ -319,7 +322,7 @@ impl WebViewRenderer {
             return;
         };
 
-        if self.pending_input_events.borrow().len() > 0 {
+        if self.epoch_not_synchronized.get() {
             self.pending_input_events.borrow_mut().push_back(event);
             return;
         }