diff --git a/public/static/js/phone-image.js b/public/static/js/phone-image.js
index 35a448e..50d1ab7 100644
--- a/public/static/js/phone-image.js
+++ b/public/static/js/phone-image.js
@@ -92,6 +92,9 @@ var PhoneImageEngine = (function () {
             $.extend(config, userConfig);
         }
 
+        // 清空缓存，避免旧数据干扰
+        convertedBlockCache = {};
+
         // 内容流事件委托（只绑定一次）
         $(document).off('click', '.break-inserter-btn');
         $(document).off('click', '.remove-break-btn');
@@ -142,6 +145,12 @@ var PhoneImageEngine = (function () {
         var cleanHtml = preprocessContent(postData.content_html);
         var blocks = parseHtmlToBlocks(cleanHtml);
 
+        // 缓存清理：如果缓存条目过多则清空，防止内存膨胀
+        var cacheKeys = Object.keys(convertedBlockCache);
+        if (cacheKeys.length > blocks.length * 3) {
+            convertedBlockCache = {};
+        }
+
         // 先渲染内容流(DOM) - 用于实测高度
         renderContentFlow(blocks);
 
@@ -181,7 +190,9 @@ var PhoneImageEngine = (function () {
                         // 如果渲染期间有新的渲染请求排队，自动触发
                         if (render._pending) {
                             render._pending = false;
-                            render();
+                            render().catch(function () {
+                                // 静默处理递归渲染失败
+                            });
                         }
                         deferred.resolve(pages);
                     }).catch(function (err) {
@@ -553,13 +564,25 @@ var PhoneImageEngine = (function () {
             return [block];
         }
 
-        // 按句子拆分：句号、问号、叹号、换行
-        var sentences = text.split(/(?<=[。！？\n])/);
+        // 按句子拆分：句号、问号、叹号、换行（兼容不支持 lookbehind 的浏览器）
+        var effectiveFontSize = parseInt(config.fontSize, 10) || 14;
+        var parts = text.split(/([。！？\n])/);
+        var sentences = [];
+        var current = '';
+        for (var si = 0; si < parts.length; si++) {
+            current += parts[si];
+            if (/[。！？\n]/.test(parts[si]) && current.length > 0) {
+                sentences.push(current);
+                current = '';
+            }
+        }
+        if (current) sentences.push(current);
+
         if (sentences.length <= 1) {
             // 无法按句子拆分，按固定字符数拆分
             sentences = [];
-            var chunkSize = Math.floor(getContentWidth() / config.fontSize) *
-                Math.floor(pageHeight / (config.fontSize * 1.8));
+            var chunkSize = Math.floor(getContentWidth() / effectiveFontSize) *
+                Math.floor(pageHeight / (effectiveFontSize * 1.8));
             if (chunkSize < 10) chunkSize = 10;
             for (var ci = 0; ci < text.length; ci += chunkSize) {
                 sentences.push(text.substring(ci, ci + chunkSize));
@@ -570,7 +593,7 @@ var PhoneImageEngine = (function () {
         for (var j = 0; j < sentences.length; j++) {
             var s = sentences[j].trim();
             if (!s) continue;
-            var h = estimateTextHeight(s, config.fontSize);
+            var h = estimateTextHeight(s, effectiveFontSize);
             result.push({
                 type: wrapperTag === 'blockquote' ? 'blockquote' : 'p',
                 html: '<' + wrapperTag + '>' + s + '</' + wrapperTag + '>',
@@ -610,7 +633,7 @@ var PhoneImageEngine = (function () {
         html += '" style="width:' + sizeConfig.width + 'px;height:' + sizeConfig.height + 'px;">';
 
         if (hasCover) {
-            html += '<img class="cover-image" src="' + postData.poster + '" alt="">';
+            html += '<img class="cover-image" src="' + escapeHtml(postData.poster) + '" alt="">';
             html += '<div class="cover-title">' + escapeHtml(postData.title) + '</div>';
             if (postData.desc) {
                 html += '<div class="cover-subtitle">' + escapeHtml(postData.desc) + '</div>';
@@ -825,7 +848,9 @@ var PhoneImageEngine = (function () {
             ? document.fonts.ready
             : $.Deferred().resolve().promise();
 
-        fontsReady.then(function () {
+        fontsReady.catch(function () {
+            // 字体加载失败不影响截图，继续执行
+        }).then(function () {
             requestAnimationFrame(function () {
                 // html2canvas会跳过visibility:hidden的元素，临时切换为可见
                 $staging.css({ visibility: 'visible' });
@@ -1163,9 +1188,16 @@ var PhoneImageEngine = (function () {
     function insertPageBreak(blockIndex) {
         // 如果正在渲染，延迟重试
         if (render._locked) {
+            insertPageBreak._retryCount = (insertPageBreak._retryCount || 0) + 1;
+            if (insertPageBreak._retryCount >= 15) {
+                insertPageBreak._retryCount = 0;
+                layer.msg('操作超时，请重试');
+                return;
+            }
             setTimeout(function () { insertPageBreak(blockIndex); }, 200);
             return;
         }
+        insertPageBreak._retryCount = 0;
 
         var cleanHtml = preprocessContent(postData.content_html);
         var $temp = $('<div>').html(cleanHtml);
@@ -1191,9 +1223,16 @@ var PhoneImageEngine = (function () {
     function removePageBreak(blockIndex) {
         // 如果正在渲染，延迟重试
         if (render._locked) {
+            removePageBreak._retryCount = (removePageBreak._retryCount || 0) + 1;
+            if (removePageBreak._retryCount >= 15) {
+                removePageBreak._retryCount = 0;
+                layer.msg('操作超时，请重试');
+                return;
+            }
             setTimeout(function () { removePageBreak(blockIndex); }, 200);
             return;
         }
+        removePageBreak._retryCount = 0;
 
         // 统计这是第几个 page-break
         var cleanHtml = preprocessContent(postData.content_html);
diff --git a/view/admin/post/phone_image.html b/view/admin/post/phone_image.html
index f16b420..a11e6b9 100644
--- a/view/admin/post/phone_image.html
+++ b/view/admin/post/phone_image.html
@@ -187,13 +187,13 @@
 
             var postData = {
                 postId: {$post.id},
-                title: '{$post.title|raw}',
-                desc: '{$post.desc|default=""}',
-                coverText: '{$post->getData("cover_text")|default=""}',
+                title: <?php echo json_encode($post->title ?? ''); ?>,
+                desc: <?php echo json_encode($post->desc ?? ''); ?>,
+                coverText: <?php echo json_encode($post->getData('cover_text') ?? ''); ?>,
                 contentHtml: $('#post-content-html').html(),
-                poster: '{$post.poster|default=""}',
-                authorName: '{$post.author_name|default=""}',
-                createTime: '{$post.create_time_text|default=""}',
+                poster: <?php echo json_encode($post->poster ?? ''); ?>,
+                authorName: <?php echo json_encode($post->author_name ?? ''); ?>,
+                createTime: <?php echo json_encode($post->create_time_text ?? ''); ?>,
                 categoryName: ''
             };