diff --git a/package.json b/package.json
index 7b8a1c44c7..684aa36bf2 100644
--- a/package.json
+++ b/package.json
@@ -229,7 +229,9 @@
     "fs-extra": "^11.2.0",
     "google-auth-library": "^9.15.1",
     "he": "^1.2.0",
+    "html-tags": "^5.1.0",
     "html-to-image": "^1.11.13",
+    "htmlparser2": "^10.0.0",
     "husky": "^9.1.7",
     "i18next": "^23.11.5",
     "iconv-lite": "^0.6.3",
diff --git a/src/renderer/src/assets/styles/richtext.scss b/src/renderer/src/assets/styles/richtext.scss
index 3890f013ec..7b4e4bdad5 100644
--- a/src/renderer/src/assets/styles/richtext.scss
+++ b/src/renderer/src/assets/styles/richtext.scss
@@ -148,6 +148,12 @@
       left: 0;
       right: 0;
     }
+
+    /* Ensure drag handles and plus buttons remain interactive */
+    .drag-handle,
+    .plus-button {
+      pointer-events: auto;
+    }
   }
 
   /* Show placeholder only when focused or when it's the only empty node */
@@ -471,6 +477,14 @@
     align-items: center;
     font-size: 1.2rem;
   }
+
+  /* Bottom spacer to create viewport padding */
+  &::after {
+    content: '';
+    display: block;
+    height: 50px;
+    pointer-events: none;
+  }
 }
 
 // Code block wrapper and header styles
diff --git a/src/renderer/src/components/CodeViewer.tsx b/src/renderer/src/components/CodeViewer.tsx
index 87a33534b9..440aed9c7c 100644
--- a/src/renderer/src/components/CodeViewer.tsx
+++ b/src/renderer/src/components/CodeViewer.tsx
@@ -17,6 +17,7 @@ interface CodeViewerProps {
   wrapped?: boolean
   onHeightChange?: (scrollHeight: number) => void
   className?: string
+  height?: string | number
 }
 
 /**
@@ -25,7 +26,7 @@ interface CodeViewerProps {
  * - 使用虚拟滚动和按需高亮，改善页面内有大量长代码块时的响应
  * - 并发安全
  */
-const CodeViewer = ({ children, language, expanded, wrapped, onHeightChange, className }: CodeViewerProps) => {
+const CodeViewer = ({ children, language, expanded, wrapped, onHeightChange, className, height }: CodeViewerProps) => {
   const { codeShowLineNumbers, fontSize } = useSettings()
   const { getShikiPreProperties, isShikiThemeDark } = useCodeStyle()
   const shikiThemeRef = useRef<HTMLDivElement>(null)
@@ -104,18 +105,20 @@ const CodeViewer = ({ children, language, expanded, wrapped, onHeightChange, cla
   }, [rawLines.length, onHeightChange])
 
   return (
-    <div ref={shikiThemeRef}>
+    <div ref={shikiThemeRef} style={height ? { height } : undefined}>
       <ScrollContainer
         ref={scrollerRef}
         className="shiki-scroller"
         $wrap={wrapped}
         $expanded={expanded}
         $lineHeight={estimateSize()}
+        $height={height}
         style={
           {
             '--gutter-width': `${gutterDigits}ch`,
             fontSize: `${fontSize - 1}px`,
-            maxHeight: expanded ? undefined : MAX_COLLAPSED_CODE_HEIGHT,
+            maxHeight: expanded ? undefined : height ? undefined : MAX_COLLAPSED_CODE_HEIGHT,
+            height: height,
             overflowY: expanded ? 'hidden' : 'auto'
           } as React.CSSProperties
         }>
@@ -225,6 +228,7 @@ const ScrollContainer = styled.div<{
   $wrap?: boolean
   $expanded?: boolean
   $lineHeight?: number
+  $height?: string | number
 }>`
   display: block;
   overflow-x: auto;
diff --git a/src/renderer/src/components/RichEditor/styles.ts b/src/renderer/src/components/RichEditor/styles.ts
index 2a1cfa8708..8c4bc608cb 100644
--- a/src/renderer/src/components/RichEditor/styles.ts
+++ b/src/renderer/src/components/RichEditor/styles.ts
@@ -61,15 +61,13 @@ export const ToolbarButton = styled.button<{
   height: 32px;
   border: none;
   border-radius: 4px;
-  background: ${({ $active }) => ($active ? 'var(--color-primary)' : 'transparent')};
-  color: ${({ $active, $disabled }) =>
-    $disabled ? 'var(--color-text-3)' : $active ? 'var(--color-white)' : 'var(--color-text)'};
+  background: transparent;
   cursor: ${({ $disabled }) => ($disabled ? 'not-allowed' : 'pointer')};
   transition: all 0.2s ease;
   flex-shrink: 0; /* 防止按钮收缩 */
 
   &:hover:not(:disabled) {
-    background: ${({ $active }) => ($active ? 'var(--color-primary)' : 'var(--color-hover)')};
+    background: var(--color-hover);
   }
 
   &:disabled {
diff --git a/src/renderer/src/components/RichEditor/toolbar.tsx b/src/renderer/src/components/RichEditor/toolbar.tsx
index a7d25efac6..ebed37349e 100644
--- a/src/renderer/src/components/RichEditor/toolbar.tsx
+++ b/src/renderer/src/components/RichEditor/toolbar.tsx
@@ -1,6 +1,7 @@
 import { Tooltip } from 'antd'
 import type { TFunction } from 'i18next'
-import React, { useEffect, useState } from 'react'
+import { LucideProps } from 'lucide-react'
+import React, { ForwardRefExoticComponent, RefAttributes, useEffect, useState } from 'react'
 import { useTranslation } from 'react-i18next'
 
 import { getCommandsByGroup } from './command'
@@ -12,7 +13,7 @@ import type { FormattingCommand, FormattingState, ToolbarProps } from './types'
 interface ToolbarItemInternal {
   id: string
   command?: FormattingCommand
-  icon?: React.ComponentType
+  icon?: ForwardRefExoticComponent<Omit<LucideProps, 'ref'> & RefAttributes<SVGSVGElement>>
   type?: 'divider'
   handler?: () => void
 }
@@ -170,7 +171,7 @@ export const Toolbar: React.FC<ToolbarProps> = ({ editor, formattingState, onCom
             disabled={isDisabled}
             onClick={() => handleCommand(command)}
             data-testid={`toolbar-${command}`}>
-            <Icon />
+            <Icon color={isActive ? 'var(--color-primary)' : 'var(--color-text)'} />
           </ToolbarButton>
         )
 
diff --git a/src/renderer/src/components/RichEditor/useRichEditor.ts b/src/renderer/src/components/RichEditor/useRichEditor.ts
index d68841b0a4..8275d3623d 100644
--- a/src/renderer/src/components/RichEditor/useRichEditor.ts
+++ b/src/renderer/src/components/RichEditor/useRichEditor.ts
@@ -8,9 +8,7 @@ import {
   htmlToMarkdown,
   isMarkdownContent,
   markdownToHtml,
-  markdownToPreviewText,
-  markdownToSafeHtml,
-  sanitizeHtml
+  markdownToPreviewText
 } from '@renderer/utils/markdownConverter'
 import type { Editor } from '@tiptap/core'
 import { TaskItem, TaskList } from '@tiptap/extension-list'
@@ -135,7 +133,7 @@ export const useRichEditor = (options: UseRichEditorOptions = {}): UseRichEditor
 
   const html = useMemo(() => {
     if (!markdown) return ''
-    return markdownToSafeHtml(markdown)
+    return markdownToHtml(markdown)
   }, [markdown])
 
   const previewText = useMemo(() => {
@@ -423,8 +421,7 @@ export const useRichEditor = (options: UseRichEditorOptions = {}): UseRichEditor
 
         onContentChange?.(content)
         if (onHtmlChange) {
-          const safeHtml = sanitizeHtml(htmlContent)
-          onHtmlChange(safeHtml)
+          onHtmlChange(htmlContent)
         }
       } catch (error) {
         logger.error('Error converting HTML to markdown:', error as Error)
@@ -502,7 +499,10 @@ export const useRichEditor = (options: UseRichEditorOptions = {}): UseRichEditor
         try {
           setTimeout(() => {
             if (editor && !editor.isDestroyed) {
-              editor.commands.focus('end')
+              const isLong = editor.getText().length > 2000
+              if (!isLong) {
+                editor.commands.focus('end')
+              }
             }
           }, 0)
         } catch (error) {
@@ -724,7 +724,7 @@ export const useRichEditor = (options: UseRichEditorOptions = {}): UseRichEditor
         setMarkdownState(content)
         onChange?.(content)
 
-        const convertedHtml = markdownToSafeHtml(content)
+        const convertedHtml = markdownToHtml(content)
 
         editor.commands.setContent(convertedHtml)
 
@@ -771,7 +771,7 @@ export const useRichEditor = (options: UseRichEditorOptions = {}): UseRichEditor
 
   const toSafeHtml = useCallback((content: string): string => {
     try {
-      return markdownToSafeHtml(content)
+      return markdownToHtml(content)
     } catch (error) {
       logger.error('Error converting markdown to safe HTML:', error as Error)
       return ''
diff --git a/src/renderer/src/pages/notes/HeaderNavbar.tsx b/src/renderer/src/pages/notes/HeaderNavbar.tsx
index 1994ae6a93..8e54b08ab4 100644
--- a/src/renderer/src/pages/notes/HeaderNavbar.tsx
+++ b/src/renderer/src/pages/notes/HeaderNavbar.tsx
@@ -109,7 +109,9 @@ const HeaderNavbar = ({ notesTree, getCurrentNoteContent }) => {
   }, [activeNode, notesTree])
 
   return (
-    <NavbarHeader className="home-navbar" style={{ justifyContent: 'flex-start' }}>
+    <NavbarHeader
+      className="home-navbar"
+      style={{ justifyContent: 'flex-start', borderBottom: '0.5px solid var(--color-border)' }}>
       <HStack alignItems="center" flex="0 0 auto">
         {showWorkspace && (
           <Tooltip title={t('navbar.hide_sidebar')} mouseEnterDelay={0.8}>
diff --git a/src/renderer/src/pages/notes/NotesEditor.tsx b/src/renderer/src/pages/notes/NotesEditor.tsx
index e181042fc6..affc5b7942 100644
--- a/src/renderer/src/pages/notes/NotesEditor.tsx
+++ b/src/renderer/src/pages/notes/NotesEditor.tsx
@@ -145,6 +145,7 @@ const RichEditorContainer = styled.div`
 
   .notes-rich-editor {
     border: none;
+    border-radius: 0;
     flex: 1;
     background: transparent;
 
@@ -173,7 +174,7 @@ const RichEditorContainer = styled.div`
 
 const BottomPanel = styled.div`
   padding: 8px 16px;
-  border-top: 1px solid var(--color-border);
+  border-top: 0.5px solid var(--color-border);
   background: var(--color-background-soft);
   flex-shrink: 0;
   height: 48px;
diff --git a/src/renderer/src/pages/notes/NotesPage.tsx b/src/renderer/src/pages/notes/NotesPage.tsx
index eb0e627323..208cc92345 100644
--- a/src/renderer/src/pages/notes/NotesPage.tsx
+++ b/src/renderer/src/pages/notes/NotesPage.tsx
@@ -53,6 +53,7 @@ const NotesPage: FC = () => {
   const isSyncingTreeRef = useRef(false)
   const isEditorInitialized = useRef(false)
   const lastContentRef = useRef<string>('')
+  const lastFilePathRef = useRef<string | undefined>(undefined)
   const isInitialSortApplied = useRef(false)
   const isRenamingRef = useRef(false)
   const isCreatingNoteRef = useRef(false)
@@ -82,13 +83,14 @@ const NotesPage: FC = () => {
 
   // 保存当前笔记内容
   const saveCurrentNote = useCallback(
-    async (content: string) => {
-      if (!activeFilePath || content === currentContent) return
+    async (content: string, filePath?: string) => {
+      const targetPath = filePath || activeFilePath
+      if (!targetPath || content === currentContent) return
 
       try {
-        await window.api.file.write(activeFilePath, content)
+        await window.api.file.write(targetPath, content)
         // 保存后立即刷新缓存，确保下次读取时获取最新内容
-        invalidateFileContent(activeFilePath)
+        invalidateFileContent(targetPath)
       } catch (error) {
         logger.error('Failed to save note:', error as Error)
       }
@@ -99,19 +101,22 @@ const NotesPage: FC = () => {
   // 防抖保存函数，在停止输入后才保存，避免输入过程中的文件写入
   const debouncedSave = useMemo(
     () =>
-      debounce((content: string) => {
-        saveCurrentNote(content)
+      debounce((content: string, filePath: string | undefined) => {
+        saveCurrentNote(content, filePath)
       }, 800), // 800ms防抖延迟
     [saveCurrentNote]
   )
 
   const handleMarkdownChange = useCallback(
     (newMarkdown: string) => {
-      // 记录最新内容，用于兜底保存
+      // 记录最新内容和文件路径，用于兜底保存
       lastContentRef.current = newMarkdown
-      debouncedSave(newMarkdown)
+      lastFilePathRef.current = activeFilePath
+      // 捕获当前文件路径，避免在防抖执行时文件路径已改变的竞态条件
+      const currentFilePath = activeFilePath
+      debouncedSave(newMarkdown, currentFilePath)
     },
-    [debouncedSave]
+    [debouncedSave, activeFilePath]
   )
 
   useEffect(() => {
@@ -148,16 +153,16 @@ const NotesPage: FC = () => {
   // 处理树同步时的状态管理
   useEffect(() => {
     if (notesTree.length === 0) return
-
     // 如果有activeFilePath但找不到对应节点，清空选择
     // 但要排除正在同步树结构、重命名或创建笔记的情况，避免在这些操作中误清空
-    if (
-      activeFilePath &&
-      !activeNode &&
-      !isSyncingTreeRef.current &&
-      !isRenamingRef.current &&
-      !isCreatingNoteRef.current
-    ) {
+    const shouldClearPath =
+      activeFilePath && !activeNode && !isSyncingTreeRef.current && !isRenamingRef.current && !isCreatingNoteRef.current
+
+    if (shouldClearPath) {
+      logger.warn('Clearing activeFilePath - node not found in tree', {
+        activeFilePath,
+        reason: 'Node not found in current tree'
+      })
       dispatch(setActiveFilePath(undefined))
     }
   }, [notesTree, activeFilePath, activeNode, dispatch])
@@ -257,8 +262,8 @@ const NotesPage: FC = () => {
       })
 
       // 如果有未保存的内容，立即保存
-      if (lastContentRef.current && lastContentRef.current !== currentContent) {
-        saveCurrentNote(lastContentRef.current).catch((error) => {
+      if (lastContentRef.current && lastContentRef.current !== currentContent && lastFilePathRef.current) {
+        saveCurrentNote(lastContentRef.current, lastFilePathRef.current).catch((error) => {
           logger.error('Emergency save failed:', error as Error)
         })
       }
@@ -288,8 +293,8 @@ const NotesPage: FC = () => {
 
   // 切换文件时重置编辑器初始化状态并兜底保存
   useEffect(() => {
-    if (lastContentRef.current && lastContentRef.current !== currentContent) {
-      saveCurrentNote(lastContentRef.current).catch((error) => {
+    if (lastContentRef.current && lastContentRef.current !== currentContent && lastFilePathRef.current) {
+      saveCurrentNote(lastContentRef.current, lastFilePathRef.current).catch((error) => {
         logger.error('Emergency save before file switch failed:', error as Error)
       })
     }
@@ -297,6 +302,7 @@ const NotesPage: FC = () => {
     // 重置状态
     isEditorInitialized.current = false
     lastContentRef.current = ''
+    lastFilePathRef.current = undefined
   }, [activeFilePath, currentContent, saveCurrentNote])
 
   // 获取目标文件夹路径（选中文件夹或根目录）
@@ -425,6 +431,7 @@ const NotesPage: FC = () => {
       if (node.type === 'file') {
         try {
           dispatch(setActiveFilePath(node.externalPath))
+          invalidateFileContent(node.externalPath)
           // 清除文件夹选择状态
           setSelectedFolderId(null)
         } catch (error) {
@@ -435,7 +442,7 @@ const NotesPage: FC = () => {
         await handleToggleExpanded(node.id)
       }
     },
-    [dispatch, handleToggleExpanded]
+    [dispatch, handleToggleExpanded, invalidateFileContent]
   )
 
   // 删除节点
diff --git a/src/renderer/src/pages/notes/NotesSidebar.tsx b/src/renderer/src/pages/notes/NotesSidebar.tsx
index 9400ad37cf..05fc76c079 100644
--- a/src/renderer/src/pages/notes/NotesSidebar.tsx
+++ b/src/renderer/src/pages/notes/NotesSidebar.tsx
@@ -522,7 +522,7 @@ const SidebarContainer = styled.div`
   width: 250px;
   height: 100vh;
   background-color: var(--color-background);
-  border-right: 1px solid var(--color-border);
+  border-right: 0.5px solid var(--color-border);
   border-top-left-radius: 10px;
   display: flex;
   flex-direction: column;
@@ -568,7 +568,7 @@ const TreeNodeContainer = styled.div<{
     if (props.active) return 'var(--color-background-soft)'
     return 'transparent'
   }};
-  border: 1px solid
+  border: 0.5px solid
     ${(props) => {
       if (props.isDragInside) return 'var(--color-primary)'
       if (props.active) return 'var(--color-border)'
@@ -669,7 +669,7 @@ const EditInput = styled(Input)`
   .ant-input {
     font-size: 13px;
     padding: 2px 6px;
-    border: 1px solid var(--color-primary);
+    border: 0.5px solid var(--color-primary);
   }
 `
 
diff --git a/src/renderer/src/pages/notes/NotesSidebarHeader.tsx b/src/renderer/src/pages/notes/NotesSidebarHeader.tsx
index 03eca39bdf..7eba3fe3c2 100644
--- a/src/renderer/src/pages/notes/NotesSidebarHeader.tsx
+++ b/src/renderer/src/pages/notes/NotesSidebarHeader.tsx
@@ -138,9 +138,10 @@ const NotesSidebarHeader: FC<NotesSidebarHeaderProps> = ({
 
 const SidebarHeader = styled.div<{ isStarView?: boolean; isSearchView?: boolean }>`
   padding: 8px 12px;
-  border-bottom: 1px solid var(--color-border);
+  border-bottom: 0.5px solid var(--color-border);
   display: flex;
   justify-content: ${(props) => (props.isStarView || props.isSearchView ? 'flex-start' : 'center')};
+  height: var(--navbar-height);
 `
 
 const HeaderActions = styled.div`
diff --git a/src/renderer/src/pages/settings/AssistantSettings/AssistantPromptSettings.tsx b/src/renderer/src/pages/settings/AssistantSettings/AssistantPromptSettings.tsx
index 034ba918c7..9f27db6afb 100644
--- a/src/renderer/src/pages/settings/AssistantSettings/AssistantPromptSettings.tsx
+++ b/src/renderer/src/pages/settings/AssistantSettings/AssistantPromptSettings.tsx
@@ -1,9 +1,10 @@
 import 'emoji-picker-element'
 
 import { CloseCircleFilled } from '@ant-design/icons'
+import CodeEditor from '@renderer/components/CodeEditor'
+import CodeViewer from '@renderer/components/CodeViewer'
 import EmojiPicker from '@renderer/components/EmojiPicker'
 import { Box, HSpaceBetweenStack, HStack } from '@renderer/components/Layout'
-import RichEditor from '@renderer/components/RichEditor'
 import { RichEditorRef } from '@renderer/components/RichEditor/types'
 import { usePromptProcessor } from '@renderer/hooks/usePromptProcessor'
 import { estimateTextTokens } from '@renderer/services/TokenService'
@@ -47,9 +48,7 @@ const AssistantPromptSettings: React.FC<Props> = ({ assistant, updateAssistant }
   })
 
   const onUpdate = () => {
-    const text = editorRef.current?.getMarkdown() || ''
-    setPrompt(text)
-    const _assistant = { ...assistant, name: name.trim(), emoji, prompt: text }
+    const _assistant = { ...assistant, name: name.trim(), emoji, prompt }
     updateAssistant(_assistant)
     window.message.success(t('common.saved'))
   }
@@ -68,13 +67,6 @@ const AssistantPromptSettings: React.FC<Props> = ({ assistant, updateAssistant }
 
   const promptVarsContent = <pre>{t('agents.add.prompt.variables.tip.content')}</pre>
 
-  const handleCommandsReady = (commandAPI: Pick<RichEditorRef, 'unregisterCommand'>) => {
-    const disabledCommands = ['image', 'inlineMath']
-    disabledCommands.forEach((commandId) => {
-      commandAPI.unregisterCommand(commandId)
-    })
-  }
-
   return (
     <Container>
       <Box mb={8} style={{ fontWeight: 'bold' }}>
@@ -129,18 +121,20 @@ const AssistantPromptSettings: React.FC<Props> = ({ assistant, updateAssistant }
       </HStack>
       <TextAreaContainer>
         <RichEditorContainer>
-          <RichEditor
-            key={showPreview ? 'preview' : 'edit'}
-            ref={editorRef}
-            initialContent={showPreview ? processedPrompt : prompt}
-            onCommandsReady={handleCommandsReady}
-            showToolbar={!showPreview}
-            editable={!showPreview}
-            showTableOfContents={false}
-            enableContentSearch={false}
-            isFullWidth={true}
-            className="prompt-rich-editor"
-          />
+          {showPreview ? (
+            <CodeViewer children={processedPrompt} language="markdown" expanded={true} height="100%" />
+          ) : (
+            <CodeEditor
+              value={prompt}
+              language="markdown"
+              onChange={setPrompt}
+              height="100%"
+              expanded={false}
+              style={{
+                height: '100%'
+              }}
+            />
+          )}
         </RichEditorContainer>
       </TextAreaContainer>
       <HSpaceBetweenStack width="100%" justifyContent="flex-end" mt="10px">
diff --git a/src/renderer/src/utils/__tests__/markdownConverter.test.ts b/src/renderer/src/utils/__tests__/markdownConverter.test.ts
index 9f42f61830..2224f7f0e7 100644
--- a/src/renderer/src/utils/__tests__/markdownConverter.test.ts
+++ b/src/renderer/src/utils/__tests__/markdownConverter.test.ts
@@ -1,6 +1,6 @@
 import { describe, expect, it } from 'vitest'
 
-import { htmlToMarkdown, markdownToHtml, markdownToSafeHtml, sanitizeHtml } from '../markdownConverter'
+import { htmlToMarkdown, markdownToHtml } from '../markdownConverter'
 
 describe('markdownConverter', () => {
   describe('htmlToMarkdown', () => {
@@ -294,33 +294,6 @@ describe('markdownConverter', () => {
     })
   })
 
-  describe('sanitizeHtml', () => {
-    it('should sanitize HTML content and remove scripts', () => {
-      const html = '<h1>Hello</h1><script>alert("xss")</script>'
-      const result = sanitizeHtml(html)
-      expect(result).toContain('<h1>Hello</h1>')
-      expect(result).not.toContain('<script>')
-      expect(result).not.toContain('alert')
-    })
-
-    it('should preserve task list HTML elements', () => {
-      const html =
-        '<ul data-type="taskList"><li data-type="taskItem" data-checked="true"><input type="checkbox" checked disabled> Task item</li></ul>'
-      const result = sanitizeHtml(html)
-      expect(result).toContain('data-type="taskList"')
-      expect(result).toContain('data-type="taskItem"')
-      expect(result).toContain('data-checked="true"')
-      expect(result).toContain('<input type="checkbox"')
-      expect(result).toContain('checked')
-      expect(result).toContain('disabled')
-    })
-
-    it('should handle empty HTML', () => {
-      const result = sanitizeHtml('')
-      expect(result).toBe('')
-    })
-  })
-
   describe('Task List with Labels', () => {
     it('should wrap task items with labels when label option is true', () => {
       const markdown = '- [ ] abcd\n\n- [x] efgh'
@@ -329,15 +302,6 @@ describe('markdownConverter', () => {
         '<ul data-type="taskList" class="task-list">\n<li data-type="taskItem" class="task-list-item" data-checked="false">\n<p><label><input type="checkbox" disabled> abcd</label></p>\n</li>\n<li data-type="taskItem" class="task-list-item" data-checked="true">\n<p><label><input type="checkbox" checked disabled> efgh</label></p>\n</li>\n</ul>\n'
       )
     })
-
-    it('should preserve labels in sanitized HTML', () => {
-      const html =
-        '<ul data-type="taskList"><li data-type="taskItem"><label><input type="checkbox" checked disabled> Task with label</label></li></ul>'
-      const result = sanitizeHtml(html)
-      expect(result).toContain('<label>')
-      expect(result).toContain('<input type="checkbox" checked')
-      expect(result).toContain('Task with label')
-    })
   })
 
   describe('Task List Round Trip', () => {
@@ -423,8 +387,8 @@ describe('markdownConverter', () => {
 
     it('should handle images with spaces in file:// protocol paths', () => {
       const markdown = '![My Image](file:///path/to/my image with spaces.png)'
-      const result = markdownToSafeHtml(markdown)
-      expect(result).toContain('<img src="file:///path/to/my image with spaces.png" alt="My Image">')
+      const result = htmlToMarkdown(markdownToHtml(markdown))
+      expect(result).toBe(markdown)
     })
 
     it('shoud img label to markdown', () => {
@@ -439,4 +403,65 @@ describe('markdownConverter', () => {
     const result = markdownToHtml(markdown)
     expect(result).toBe('<p>Text with <br />\nindentation <br />\nand without indentation</p>\n')
   })
+
+  describe('Custom XML Tags Preservation', () => {
+    it('should preserve custom XML tags through markdown-to-HTML and HTML-to-markdown conversion', () => {
+      const markdown = 'Some text with <custom-tag>content</custom-tag> and more text'
+      const html = markdownToHtml(markdown)
+      const backToMarkdown = htmlToMarkdown(html)
+
+      expect(html).toContain('Some text with <custom-tag>content</custom-tag> and more text')
+      expect(backToMarkdown).toBe('Some text with <custom-tag>content</custom-tag> and more text')
+    })
+
+    it('should preserve single custom XML tags', () => {
+      const markdown = '<abc>'
+      const html = markdownToHtml(markdown)
+      const backToMarkdown = htmlToMarkdown(html)
+
+      expect(html).toBe('<p><abc></p>')
+      expect(backToMarkdown).toBe('<abc>')
+    })
+
+    it('should preserve single custom XML tags in html', () => {
+      const html = '<p><abc></p>'
+      const markdown = htmlToMarkdown(html)
+      const backToHtml = markdownToHtml(markdown)
+
+      expect(markdown).toBe('<abc>')
+      expect(backToHtml).toBe('<p><abc></p>')
+    })
+
+    it('should preserve custom XML tags mixed with regular markdown', () => {
+      const markdown = '# Heading\n\n<custom-widget id="widget1">Widget content</custom-widget>\n\n**Bold text**'
+      const html = markdownToHtml(markdown)
+      const backToMarkdown = htmlToMarkdown(html)
+
+      expect(html).toContain('<h1>Heading</h1>')
+      expect(html).toContain('<custom-widget id="widget1">Widget content</custom-widget>')
+      expect(html).toContain('<strong>Bold text</strong>')
+      expect(backToMarkdown).toContain('# Heading')
+      expect(backToMarkdown).toContain('<custom-widget id="widget1">Widget content</custom-widget>')
+      expect(backToMarkdown).toContain('**Bold text**')
+    })
+  })
+
+  describe('Typing behavior issues', () => {
+    it('should not add unwanted line breaks during simple text typing', () => {
+      const html = '<p>Hello world</p>'
+      const markdown = htmlToMarkdown(html)
+      const backToHtml = markdownToHtml(markdown)
+
+      expect(markdown).toBe('Hello world')
+      expect(backToHtml).toBe('<p>Hello world</p>\n')
+    })
+
+    it('should preserve simple paragraph structure during round-trip conversion', () => {
+      const originalHtml = '<p>This is a simple paragraph being typed</p>'
+      const markdown = htmlToMarkdown(originalHtml)
+      const backToHtml = markdownToHtml(markdown)
+      expect(markdown).toBe('This is a simple paragraph being typed')
+      expect(backToHtml).toBe('<p>This is a simple paragraph being typed</p>\n')
+    })
+  })
 })
diff --git a/src/renderer/src/utils/markdownConverter.ts b/src/renderer/src/utils/markdownConverter.ts
index 0b905689b8..50a7f4c186 100644
--- a/src/renderer/src/utils/markdownConverter.ts
+++ b/src/renderer/src/utils/markdownConverter.ts
@@ -1,13 +1,77 @@
 import { loggerService } from '@logger'
 import { TurndownPlugin } from '@truto/turndown-plugin-gfm'
-import DOMPurify from 'dompurify'
 import he from 'he'
+import htmlTags, { type HtmlTags } from 'html-tags'
+import * as htmlparser2 from 'htmlparser2'
 import MarkdownIt from 'markdown-it'
 import striptags from 'striptags'
 import TurndownService from 'turndown'
 
 const logger = loggerService.withContext('markdownConverter')
 
+function escapeCustomTags(html: string) {
+  let result = ''
+  let currentPos = 0
+  const processedPositions = new Set<number>()
+
+  const parser = new htmlparser2.Parser({
+    onopentagname(tagname) {
+      const startPos = parser.startIndex
+      const endPos = parser.endIndex
+
+      // Add content before this tag
+      result += html.slice(currentPos, startPos)
+
+      if (!htmlTags.includes(tagname as HtmlTags)) {
+        // This is a custom tag, escape it
+        const tagHtml = html.slice(startPos, endPos + 1)
+        result += tagHtml.replace(/</g, '&lt;').replace(/>/g, '&gt;')
+      } else {
+        // This is a standard HTML tag, keep it as-is
+        result += html.slice(startPos, endPos + 1)
+      }
+
+      currentPos = endPos + 1
+    },
+
+    onclosetag(tagname) {
+      const startPos = parser.startIndex
+      const endPos = parser.endIndex
+
+      // Skip if we've already processed this position (handles malformed HTML)
+      if (processedPositions.has(endPos) || endPos + 1 <= currentPos) {
+        return
+      }
+
+      processedPositions.add(endPos)
+
+      // Get the actual HTML content at this position to verify what tag it really is
+      const actualTagHtml = html.slice(startPos, endPos + 1)
+      const actualTagMatch = actualTagHtml.match(/<\/([^>]+)>/)
+      const actualTagName = actualTagMatch ? actualTagMatch[1] : tagname
+
+      if (!htmlTags.includes(actualTagName as HtmlTags)) {
+        // This is a custom tag, escape it
+        result += html.slice(currentPos, startPos)
+        result += actualTagHtml.replace(/</g, '&lt;').replace(/>/g, '&gt;')
+        currentPos = endPos + 1
+      } else {
+        // This is a standard HTML tag, add content up to and including the closing tag
+        result += html.slice(currentPos, endPos + 1)
+        currentPos = endPos + 1
+      }
+    },
+
+    onend() {
+      result += html.slice(currentPos)
+    }
+  })
+
+  parser.write(html)
+  parser.end()
+  return result
+}
+
 export interface TaskListOptions {
   label?: boolean
 }
@@ -537,7 +601,10 @@ export const htmlToMarkdown = (html: string | null | undefined): string => {
   }
 
   try {
-    return turndownService.turndown(html).trim()
+    const encodedHtml = escapeCustomTags(html)
+    const turndownResult = turndownService.turndown(encodedHtml).trim()
+    const finalResult = he.decode(turndownResult)
+    return finalResult
   } catch (error) {
     logger.error('Error converting HTML to Markdown:', error as Error)
     return ''
@@ -572,94 +639,24 @@ export const markdownToHtml = (markdown: string | null | undefined): string => {
       }
     )
 
-    return md.render(processedMarkdown)
+    let html = md.render(processedMarkdown)
+    const trimmedMarkdown = processedMarkdown.trim()
+    if (html.trim() === trimmedMarkdown) {
+      const singleTagMatch = trimmedMarkdown.match(/^<([a-zA-Z][^>\s]*)\/?>$/)
+      if (singleTagMatch) {
+        const tagName = singleTagMatch[1]
+        if (!htmlTags.includes(tagName.toLowerCase() as any)) {
+          html = `<p>${html}</p>`
+        }
+      }
+    }
+    return html
   } catch (error) {
     logger.error('Error converting Markdown to HTML:', error as Error)
     return ''
   }
 }
 
-/**
- * Sanitizes HTML content using DOMPurify
- * @param html - HTML string to sanitize
- * @returns Sanitized HTML string
- */
-export const sanitizeHtml = (html: string): string => {
-  if (!html || typeof html !== 'string') {
-    return ''
-  }
-
-  return DOMPurify.sanitize(html, {
-    ALLOWED_TAGS: [
-      'h1',
-      'h2',
-      'h3',
-      'h4',
-      'h5',
-      'h6',
-      'div',
-      'span',
-      'p',
-      'br',
-      'hr',
-      'strong',
-      'b',
-      'em',
-      'i',
-      'u',
-      's',
-      'del',
-      'ul',
-      'ol',
-      'li',
-      'blockquote',
-      'code',
-      'pre',
-      'a',
-      'img',
-      'table',
-      'thead',
-      'tbody',
-      'tfoot',
-      'tr',
-      'td',
-      'th',
-      'input',
-      'label',
-      'details',
-      'summary'
-    ],
-    ALLOWED_ATTR: [
-      'href',
-      'title',
-      'alt',
-      'src',
-      'class',
-      'id',
-      'colspan',
-      'rowspan',
-      'type',
-      'checked',
-      'disabled',
-      'width',
-      'height',
-      'loading'
-    ],
-    ALLOW_DATA_ATTR: true,
-    ALLOWED_URI_REGEXP: /^(?:(?:(?:f|ht)tps?|file|mailto|tel|callto|cid|xmpp):|[^a-z]|[a-z+.\\-]+(?:[^a-z+.\-:]|$))/i
-  })
-}
-
-/**
- * Converts Markdown to safe HTML (combines conversion and sanitization)
- * @param markdown - Markdown string to convert
- * @returns Safe HTML string
- */
-export const markdownToSafeHtml = (markdown: string): string => {
-  const html = markdownToHtml(markdown)
-  return sanitizeHtml(html)
-}
-
 /**
  * Gets plain text preview from Markdown content
  * @param markdown - Markdown string
diff --git a/yarn.lock b/yarn.lock
index c92401668c..96f37725a6 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -9509,7 +9509,9 @@ __metadata:
     google-auth-library: "npm:^9.15.1"
     graceful-fs: "npm:^4.2.11"
     he: "npm:^1.2.0"
+    html-tags: "npm:^5.1.0"
     html-to-image: "npm:^1.11.13"
+    htmlparser2: "npm:^10.0.0"
     husky: "npm:^9.1.7"
     i18next: "npm:^23.11.5"
     iconv-lite: "npm:^0.6.3"
@@ -12442,7 +12444,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"domutils@npm:^3.0.1":
+"domutils@npm:^3.0.1, domutils@npm:^3.2.1":
   version: 3.2.2
   resolution: "domutils@npm:3.2.2"
   dependencies:
@@ -14880,6 +14882,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"html-tags@npm:^5.1.0":
+  version: 5.1.0
+  resolution: "html-tags@npm:5.1.0"
+  checksum: 10c0/2dda19bc07e75837d0c52984558d92e8b82768050e4d6421b3164b1cb6ca5e73719209c2b23c0fa71faf097a7a3d18cf7f2021b488f1b1f270fca516c4c634c9
+  languageName: node
+  linkType: hard
+
 "html-to-image@npm:^1.11.13":
   version: 1.11.13
   resolution: "html-to-image@npm:1.11.13"
@@ -14914,6 +14923,18 @@ __metadata:
   languageName: node
   linkType: hard
 
+"htmlparser2@npm:^10.0.0":
+  version: 10.0.0
+  resolution: "htmlparser2@npm:10.0.0"
+  dependencies:
+    domelementtype: "npm:^2.3.0"
+    domhandler: "npm:^5.0.3"
+    domutils: "npm:^3.2.1"
+    entities: "npm:^6.0.0"
+  checksum: 10c0/47cfa37e529c86a7ba9a1e0e6f951ad26ef8ca5af898ab6e8916fa02c0264c1453b4a65f28b7b8a7f9d0d29b5a70abead8203bf8b3f07bc69407e85e7d9a68e4
+  languageName: node
+  linkType: hard
+
 "htmlparser2@npm:^8.0.2":
   version: 8.0.2
   resolution: "htmlparser2@npm:8.0.2"