diff --git a/static/css/login.css b/static/css/login.css
index ea762c6..48a725a 100644
--- a/static/css/login.css
+++ b/static/css/login.css
@@ -581,18 +581,30 @@ input:focus {
   border-radius: 18px;
   background: #f8fbff;
   line-height: 1.7;
+  min-width: 0;
+  max-width: 100%;
+  overflow-wrap: anywhere;
+  word-break: break-word;
 }
 
 .message-bubble p,
 .message-content p {
   margin: 0;
   line-height: 1.8;
+  min-width: 0;
+  max-width: 100%;
+  overflow-wrap: anywhere;
+  word-break: break-word;
 }
 
 .message-content {
   display: grid;
   gap: 14px;
   line-height: 1.8;
+  min-width: 0;
+  max-width: 100%;
+  overflow-wrap: anywhere;
+  word-break: break-word;
 }
 
 .message-content a {
@@ -963,6 +975,7 @@ input:focus {
   border-collapse: collapse;
   font-size: 13px;
   line-height: 1.6;
+  table-layout: fixed;
 }
 
 .message-bubble th,
@@ -971,6 +984,21 @@ input:focus {
   border: 1px solid var(--line);
   text-align: left;
   vertical-align: top;
+  overflow-wrap: anywhere;
+  word-break: break-word;
+}
+
+.message-bubble pre {
+  max-width: 100%;
+  overflow-x: auto;
+  white-space: pre-wrap;
+  overflow-wrap: anywhere;
+}
+
+.message-bubble code {
+  white-space: pre-wrap;
+  overflow-wrap: anywhere;
+  word-break: break-word;
 }
 
 @media (max-width: 980px) {
diff --git a/static/js/app.js b/static/js/app.js
index a87c4b2..79d9cf6 100644
--- a/static/js/app.js
+++ b/static/js/app.js
@@ -18,6 +18,8 @@
   var uploadStatus = document.getElementById("uploadStatus");
   var workflowCardList = document.getElementById("workflowCardList");
   var nodeAnchors = [];
+  var workflowPollingTimers = {};
+  var WORKFLOW_POLL_INTERVAL_MS = 1500;
 
   if (!workspace) {
     return;
@@ -236,10 +238,15 @@
   }
 
   function renderAssistantContent(text) {
-    if (window.marked && window.DOMPurify) {
-      return window.DOMPurify.sanitize(window.marked.parse(text || ""));
+    try {
+      if (window.marked && window.DOMPurify) {
+        return window.DOMPurify.sanitize(window.marked.parse(text || ""));
+      }
+      return renderBasicMarkdown(text || "");
+    } catch (error) {
+      console.error("Markdown render failed", error);
+      return nl2br(text || "");
     }
-    return renderBasicMarkdown(text || "");
   }
 
   function renderExistingAssistantMessages() {
@@ -313,7 +320,7 @@
       return;
     }
     var encodedTitle = title;
-    var existing = document.querySelector('.history-item[href*="conversation=' + conversationId + '"]');
+    var existing = document.querySelector('.history-item[data-conversation-id="' + conversationId + '"]');
     var list = document.querySelector(".history-list");
     var currentTime = new Date();
     var month = String(currentTime.getMonth() + 1).padStart(2, "0");
@@ -347,6 +354,7 @@
 
     var item = document.createElement("a");
     item.className = "history-item active";
+    item.setAttribute("data-conversation-id", conversationId);
     item.href = "/?conversation=" + conversationId;
     item.innerHTML =
       '<span class="history-title">' +
@@ -496,11 +504,20 @@
 
   async function refreshWorkflowCard(batchId) {
     if (!summaryPanel || !batchId) {
-      return;
+      return "";
+    }
+    var response;
+    try {
+      response = await fetch(templateUrl("data-status-url-template", "__batch_id__", batchId), {
+        cache: "no-store",
+      });
+    } catch (error) {
+      console.error("Workflow status refresh failed", { batchId: batchId, error: error });
+      return "";
     }
-    var response = await fetch(templateUrl("data-status-url-template", "__batch_id__", batchId));
     if (!response.ok) {
-      return;
+      console.error("Workflow status refresh returned non-OK", { batchId: batchId, status: response.status });
+      return "";
     }
     var payload = await response.json();
     var card = ensureWorkflowCard({
@@ -508,7 +525,7 @@
       batch_no: payload.batch.batch_no,
     });
     if (!card) {
-      return;
+      return payload.batch.status || "";
     }
     var status = card.querySelector(".workflow-status");
     status.textContent = payload.batch.status;
@@ -522,6 +539,50 @@
       item.innerHTML = "<span>" + escapeHtml(node.node_name) + "</span><em>" + node.progress + "%</em>";
       list.appendChild(item);
     });
+    return payload.batch.status || "";
+  }
+
+  function isWorkflowTerminalStatus(status) {
+    return status === "success" || status === "failed";
+  }
+
+  function stopWorkflowPolling(batchId) {
+    if (!workflowPollingTimers[batchId]) {
+      return;
+    }
+    window.clearInterval(workflowPollingTimers[batchId]);
+    delete workflowPollingTimers[batchId];
+  }
+
+  function startWorkflowPolling(batchId) {
+    if (!batchId || workflowPollingTimers[batchId]) {
+      return;
+    }
+    workflowPollingTimers[batchId] = window.setInterval(async function () {
+      var status = await refreshWorkflowCard(batchId);
+      if (isWorkflowTerminalStatus(status)) {
+        stopWorkflowPolling(batchId);
+      }
+    }, WORKFLOW_POLL_INTERVAL_MS);
+    refreshWorkflowCard(batchId).then(function (status) {
+      if (isWorkflowTerminalStatus(status)) {
+        stopWorkflowPolling(batchId);
+      }
+    });
+  }
+
+  function refreshRunningWorkflowCards() {
+    if (!workflowCardList) {
+      return;
+    }
+    workflowCardList.querySelectorAll(".workflow-card").forEach(function (card) {
+      var batchId = card.getAttribute("data-batch-id");
+      var status = card.querySelector(".workflow-status");
+      var statusText = status ? status.textContent.trim() : "";
+      if (!isWorkflowTerminalStatus(statusText)) {
+        startWorkflowPolling(batchId);
+      }
+    });
   }
 
   async function streamChat(event) {
@@ -597,7 +658,13 @@
             return;
           }
 
-          var payload = JSON.parse(dataText);
+          var payload;
+          try {
+            payload = JSON.parse(dataText);
+          } catch (error) {
+            console.error("SSE frame parse failed", { error: error, frame: frame });
+            return;
+          }
           if (eventName === "meta") {
             if (payload.conversation_id) {
               conversationIdInput.value = payload.conversation_id;
@@ -616,7 +683,7 @@
             assistantMessage.text.innerHTML = renderAssistantContent(assistantText);
           } else if (eventName === "workflow_started") {
             ensureWorkflowCard(payload);
-            refreshWorkflowCard(payload.batch_id);
+            startWorkflowPolling(payload.batch_id);
           } else if (eventName === "done") {
             if (payload.assistant_message_id) {
               assistantMessage.article.id = "message-" + payload.assistant_message_id;
@@ -647,6 +714,7 @@
   syncNodeRailVisibility();
   bindNodeAnchorClicks();
   renderExistingAssistantMessages();
+  refreshRunningWorkflowCards();
 
   if (chatScroll) {
     chatScroll.addEventListener("scroll", setActiveNode, { passive: true });
diff --git a/templates/home.html b/templates/home.html
index e88a4d7..9c6d482 100644
--- a/templates/home.html
+++ b/templates/home.html
@@ -74,6 +74,7 @@
         {% for conversation in conversations %}
           <a
             class="history-item{% if current_conversation and current_conversation.pk == conversation.pk %} active{% endif %}"
+            data-conversation-id="{{ conversation.pk }}"
             href="/?conversation={{ conversation.pk }}{% if search_query %}&q={{ search_query|urlencode }}{% endif %}"
           >
             <span class="history-title">{{ conversation.title|default:"新对话" }}</span>
diff --git a/tests/test_file_summary_frontend.py b/tests/test_file_summary_frontend.py
index a638aa8..4f46de1 100644
--- a/tests/test_file_summary_frontend.py
+++ b/tests/test_file_summary_frontend.py
@@ -24,6 +24,31 @@ def test_workspace_renders_summary_panel(client, django_user_model):
     assert 'id="summaryPanel"' in content
     assert 'id="uploadDropzone"' in content
     assert 'id="workflowCardList"' in content
+    assert 'data-conversation-id="' in content
     assert 'class="message-content markdown-content"' in content
     assert 'class="message-raw"' in content
     assert "自动汇总文件目录与页数" in content
+
+
+def test_frontend_prevents_long_message_overflow():
+    css = open("static/css/login.css", encoding="utf-8").read()
+
+    assert ".message-bubble" in css
+    assert "overflow-wrap: anywhere" in css
+    assert "word-break: break-word" in css
+
+
+def test_frontend_polls_running_workflow_cards():
+    script = open("static/js/app.js", encoding="utf-8").read()
+
+    assert "startWorkflowPolling" in script
+    assert "setInterval" in script
+    assert "refreshRunningWorkflowCards" in script
+
+
+def test_frontend_updates_sidebar_conversation_by_stable_id():
+    script = open("static/js/app.js", encoding="utf-8").read()
+
+    assert "data-conversation-id" in script
+    assert "setAttribute(\"data-conversation-id\"" in script
+    assert ".history-item[data-conversation-id=" in script