From aa5293de22bba11777956f1d6e8169118249fb3e Mon Sep 17 00:00:00 2001
From: Max Brunsfeld <maxbrunsfeld@gmail.com>
Date: Mon, 20 Apr 2026 16:15:01 -0700
Subject: [PATCH] Avoid constantly scrolling thread history to top as agent
 generates (#54365)

Fixes two problems:

* We were not preserving scroll position in the thread history view when
the thread metadata store updated
* We were updating thread metadata on every single chunk streamed by the
agent, even though the content of the thread does not affect its
metadata.

Release Notes:

- N/A
---
 crates/agent_ui/src/conversation_view.rs    |  8 ++++----
 crates/agent_ui/src/threads_archive_view.rs | 10 +++-------
 2 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/crates/agent_ui/src/conversation_view.rs b/crates/agent_ui/src/conversation_view.rs
index 2ce8f7d73dfea301923f8a667d3d42088162cc00..b796f6dcfcf26d054ba79079f8dc8a885b911991 100644
--- a/crates/agent_ui/src/conversation_view.rs
+++ b/crates/agent_ui/src/conversation_view.rs
@@ -396,18 +396,18 @@ fn affects_thread_metadata(event: &AcpThreadEvent) -> bool {
     match event {
         AcpThreadEvent::NewEntry
         | AcpThreadEvent::TitleUpdated
-        | AcpThreadEvent::EntryUpdated(_)
-        | AcpThreadEvent::EntriesRemoved(_)
         | AcpThreadEvent::ToolAuthorizationRequested(_)
         | AcpThreadEvent::ToolAuthorizationReceived(_)
-        | AcpThreadEvent::Retry(_)
         | AcpThreadEvent::Stopped(_)
         | AcpThreadEvent::Error
         | AcpThreadEvent::LoadError(_)
         | AcpThreadEvent::Refusal
         | AcpThreadEvent::WorkingDirectoriesUpdated => true,
         // --
-        AcpThreadEvent::TokenUsageUpdated
+        AcpThreadEvent::EntryUpdated(_)
+        | AcpThreadEvent::EntriesRemoved(_)
+        | AcpThreadEvent::Retry(_)
+        | AcpThreadEvent::TokenUsageUpdated
         | AcpThreadEvent::PromptCapabilitiesUpdated
         | AcpThreadEvent::AvailableCommandsUpdated(_)
         | AcpThreadEvent::ModeUpdated(_)
diff --git a/crates/agent_ui/src/threads_archive_view.rs b/crates/agent_ui/src/threads_archive_view.rs
index 6547187547c839bb1b804f933296089ffd435c28..b86d19f2013442690ebc3ca80afb71ae8b576e0e 100644
--- a/crates/agent_ui/src/threads_archive_view.rs
+++ b/crates/agent_ui/src/threads_archive_view.rs
@@ -320,11 +320,7 @@ impl ThreadsArchiveView {
         let preserve = self.preserve_selection_on_next_update;
         self.preserve_selection_on_next_update = false;
 
-        let saved_scroll = if preserve {
-            Some(self.list_state.logical_scroll_top())
-        } else {
-            None
-        };
+        let saved_scroll = self.list_state.logical_scroll_top();
 
         self.list_state.reset(items.len());
         self.items = items;
@@ -337,9 +333,9 @@ impl ThreadsArchiveView {
             }
         }
 
-        if let Some(scroll_top) = saved_scroll {
-            self.list_state.scroll_to(scroll_top);
+        self.list_state.scroll_to(saved_scroll);
 
+        if preserve {
             if let Some(ix) = self.selection {
                 let next = self.find_next_selectable(ix).or_else(|| {
                     ix.checked_sub(1)