diff --git a/apps/x/apps/renderer/src/components/markdown-editor.tsx b/apps/x/apps/renderer/src/components/markdown-editor.tsx
index ee838d41..3d22c646 100644
--- a/apps/x/apps/renderer/src/components/markdown-editor.tsx
+++ b/apps/x/apps/renderer/src/components/markdown-editor.tsx
@@ -10,7 +10,7 @@ import TaskItem from '@tiptap/extension-task-item'
 import { ImageUploadPlaceholderExtension, createImageUploadHandler } from '@/extensions/image-upload'
 import { TaskBlockExtension } from '@/extensions/task-block'
 import { TrackBlockExtension } from '@/extensions/track-block'
-import { TrackTargetExtension } from '@/extensions/track-target'
+import { TrackTargetOpenExtension, TrackTargetCloseExtension } from '@/extensions/track-target'
 import { ImageBlockExtension } from '@/extensions/image-block'
 import { EmbedBlockExtension } from '@/extensions/embed-block'
 import { ChartBlockExtension } from '@/extensions/chart-block'
@@ -44,20 +44,29 @@ function preprocessMarkdown(markdown: string): string {
   })
 }
 
-// Convert each `<!--track-target:ID-->...<!--/track-target:ID-->` region to a
-// placeholder HTML element that Tiptap's TrackTargetExtension parses into a
-// `trackTarget` node. Content is base64-encoded so any characters survive.
-// Without this step, tiptap-markdown strips the comment markers and leaves the
-// inner content as loose paragraphs, which then duplicates when the backend
-// re-inserts fresh markers around new content.
+// Convert track-target open/close HTML comment markers into placeholder divs
+// that TrackTargetOpenExtension / TrackTargetCloseExtension pick up as atom
+// nodes. Content *between* the markers is left untouched — tiptap-markdown
+// parses it naturally as whatever it is (paragraphs, lists, custom-block
+// fences, etc.), all rendered live by the existing extension set.
+//
+// CommonMark rule: a type-6 HTML block (div, etc.) runs from the opening tag
+// line until a blank line terminates it, and markdown inline rules (bold,
+// italics, links) don't apply inside the block. Without surrounding blank
+// lines, the line right after our placeholder div gets absorbed as HTML and
+// its markdown is not parsed. We consume any adjacent newlines in the match
+// and emit exactly `\n\n<div></div>\n\n` so the HTML block starts and ends on
+// its own line.
 function preprocessTrackTargets(md: string): string {
-  return md.replace(
-    /<!--track-target:([^\s>]+)-->\n?([\s\S]*?)\n?<!--\/track-target:\1-->/g,
-    (_match, id: string, content: string) => {
-      const b64 = btoa(unescape(encodeURIComponent(content)))
-      return `<div data-type="track-target" data-track-id="${id}" data-content="${b64}"></div>`
-    },
-  )
+  return md
+    .replace(
+      /\n?<!--track-target:([^\s>]+)-->\n?/g,
+      (_m, id: string) => `\n\n<div data-type="track-target-open" data-track-id="${id}"></div>\n\n`,
+    )
+    .replace(
+      /\n?<!--\/track-target:([^\s>]+)-->\n?/g,
+      (_m, id: string) => `\n\n<div data-type="track-target-close" data-track-id="${id}"></div>\n\n`,
+    )
 }
 
 // Post-process to clean up any zero-width spaces in the output
@@ -160,11 +169,10 @@ function blockToMarkdown(node: JsonNode): string {
       return '```task\n' + (node.attrs?.data as string || '{}') + '\n```'
     case 'trackBlock':
       return '```track\n' + (node.attrs?.data as string || '') + '\n```'
-    case 'trackTarget': {
-      const id = (node.attrs?.trackId as string) ?? ''
-      const content = (node.attrs?.content as string) ?? ''
-      return `<!--track-target:${id}-->\n${content}\n<!--/track-target:${id}-->`
-    }
+    case 'trackTargetOpen':
+      return `<!--track-target:${(node.attrs?.trackId as string) ?? ''}-->`
+    case 'trackTargetClose':
+      return `<!--/track-target:${(node.attrs?.trackId as string) ?? ''}-->`
     case 'imageBlock':
       return '```image\n' + (node.attrs?.data as string || '{}') + '\n```'
     case 'embedBlock':
@@ -664,7 +672,8 @@ export const MarkdownEditor = forwardRef<MarkdownEditorHandle, MarkdownEditorPro
       ImageUploadPlaceholderExtension,
       TaskBlockExtension,
       TrackBlockExtension.configure({ notePath }),
-      TrackTargetExtension,
+      TrackTargetOpenExtension,
+      TrackTargetCloseExtension,
       ImageBlockExtension,
       EmbedBlockExtension,
       ChartBlockExtension,
diff --git a/apps/x/apps/renderer/src/extensions/track-target.tsx b/apps/x/apps/renderer/src/extensions/track-target.tsx
index 98d5541a..8b092c74 100644
--- a/apps/x/apps/renderer/src/extensions/track-target.tsx
+++ b/apps/x/apps/renderer/src/extensions/track-target.tsx
@@ -1,117 +1,90 @@
 import { mergeAttributes, Node } from '@tiptap/react'
-import { ReactNodeViewRenderer, NodeViewWrapper } from '@tiptap/react'
-import { Streamdown } from 'streamdown'
 
 /**
- * TrackTargetExtension — a Tiptap atom node that owns a
- *   <!--track-target:ID-->...<!--/track-target:ID-->
- * region. Content is display-only; the backend is the sole writer.
+ * Track target markers — two Tiptap atom nodes that represent the open and
+ * close HTML comment markers bracketing a track's output region on disk:
  *
- * Parse path: `markdown-editor.tsx#preprocessTrackTargets` converts each
- * comment-wrapped region into a placeholder
- *   <div data-type="track-target" data-track-id="..." data-content="<base64>"></div>
- * which the `parseHTML` rule below picks up.
+ *   <!--track-target:ID-->   →  TrackTargetOpenExtension
+ *   content in between       →  regular Tiptap nodes (paragraphs, lists,
+ *                                custom blocks, whatever tiptap-markdown parses)
+ *   <!--/track-target:ID-->  →  TrackTargetCloseExtension
  *
- * Serialize path: round-trips back to the exact comment-wrapped form via
- * `addStorage().markdown.serialize` AND via the custom
- * `blockToMarkdown` switch in `markdown-editor.tsx` (both save paths must
- * handle it identically).
+ * The markers are *semantic boundaries*, not a UI container. Content between
+ * them is real, editable document content — fully rendered by the existing
+ * extension set and freely editable by the user. The backend's updateContent()
+ * in fileops.ts still locates the region on disk by these comment markers.
+ *
+ * Load path: `markdown-editor.tsx#preprocessTrackTargets` does a per-marker
+ * regex replace, converting each comment into a placeholder div that these
+ * extensions' parseHTML rules pick up. No content capture.
+ *
+ * Save path: both Tiptap's built-in markdown serializer
+ * (`addStorage().markdown.serialize`) AND the app's custom serializer
+ * (`blockToMarkdown` in markdown-editor.tsx) write the original comment form
+ * back out — they must stay in sync.
  */
 
-// Unicode-safe base64 helpers — content may contain any char, including
-// emoji and CJK. btoa/atob alone only handle Latin-1.
-function encode(s: string): string {
-  return btoa(unescape(encodeURIComponent(s)))
+type MarkerVariant = 'open' | 'close'
+
+function buildMarkerExtension(variant: MarkerVariant) {
+    const name = variant === 'open' ? 'trackTargetOpen' : 'trackTargetClose'
+    const htmlType = variant === 'open' ? 'track-target-open' : 'track-target-close'
+    const commentFor = (id: string) =>
+        variant === 'open' ? `<!--track-target:${id}-->` : `<!--/track-target:${id}-->`
+
+    return Node.create({
+        name,
+        group: 'block',
+        atom: true,
+        selectable: true,
+        draggable: false,
+
+        addAttributes() {
+            return {
+                trackId: { default: '' },
+            }
+        },
+
+        parseHTML() {
+            return [
+                {
+                    tag: `div[data-type="${htmlType}"]`,
+                    getAttrs(el) {
+                        if (!(el instanceof HTMLElement)) return false
+                        return { trackId: el.getAttribute('data-track-id') ?? '' }
+                    },
+                },
+            ]
+        },
+
+        renderHTML({ HTMLAttributes, node }: { HTMLAttributes: Record<string, unknown>; node: { attrs: Record<string, unknown> } }) {
+            return [
+                'div',
+                mergeAttributes(HTMLAttributes, {
+                    'data-type': htmlType,
+                    'data-track-id': (node.attrs.trackId as string) ?? '',
+                }),
+            ]
+        },
+
+        addStorage() {
+            return {
+                markdown: {
+                    serialize(
+                        state: { write: (text: string) => void; closeBlock: (node: unknown) => void },
+                        node: { attrs: { trackId: string } },
+                    ) {
+                        state.write(commentFor(node.attrs.trackId ?? ''))
+                        state.closeBlock(node)
+                    },
+                    parse: {
+                        // handled via preprocessTrackTargets → parseHTML
+                    },
+                },
+            }
+        },
+    })
 }
 
-function decode(s: string): string {
-  try {
-    return decodeURIComponent(escape(atob(s)))
-  } catch {
-    return ''
-  }
-}
-
-function TrackTargetView({ node }: {
-  node: { attrs: Record<string, unknown> }
-}) {
-  const trackId = (node.attrs.trackId as string) ?? ''
-  const content = (node.attrs.content as string) ?? ''
-
-  return (
-    <NodeViewWrapper
-      className="track-target-wrapper"
-      data-type="track-target"
-      data-track-id={trackId}
-    >
-      <div className="track-target-box" onMouseDown={(e) => e.stopPropagation()}>
-        {content.trim()
-          ? <Streamdown className="track-target-markdown">{content}</Streamdown>
-          : <span className="track-target-empty">No output yet — run the track to populate this area.</span>}
-      </div>
-    </NodeViewWrapper>
-  )
-}
-
-export const TrackTargetExtension = Node.create({
-  name: 'trackTarget',
-  group: 'block',
-  atom: true,
-  selectable: true,
-  draggable: false,
-
-  addAttributes() {
-    return {
-      trackId: { default: '' },
-      content: { default: '' },
-    }
-  },
-
-  parseHTML() {
-    return [
-      {
-        tag: 'div[data-type="track-target"]',
-        getAttrs(el) {
-          if (!(el instanceof HTMLElement)) return false
-          const trackId = el.getAttribute('data-track-id') ?? ''
-          const b64 = el.getAttribute('data-content') ?? ''
-          return { trackId, content: b64 ? decode(b64) : '' }
-        },
-      },
-    ]
-  },
-
-  renderHTML({ HTMLAttributes, node }: { HTMLAttributes: Record<string, unknown>; node: { attrs: Record<string, unknown> } }) {
-    return [
-      'div',
-      mergeAttributes(HTMLAttributes, {
-        'data-type': 'track-target',
-        'data-track-id': (node.attrs.trackId as string) ?? '',
-        'data-content': encode((node.attrs.content as string) ?? ''),
-      }),
-    ]
-  },
-
-  addNodeView() {
-    return ReactNodeViewRenderer(TrackTargetView)
-  },
-
-  addStorage() {
-    return {
-      markdown: {
-        serialize(
-          state: { write: (text: string) => void; closeBlock: (node: unknown) => void },
-          node: { attrs: { trackId: string; content: string } },
-        ) {
-          const id = node.attrs.trackId ?? ''
-          const content = node.attrs.content ?? ''
-          state.write(`<!--track-target:${id}-->\n${content}\n<!--/track-target:${id}-->`)
-          state.closeBlock(node)
-        },
-        parse: {
-          // handled by parseHTML after preprocessTrackTargets runs
-        },
-      },
-    }
-  },
-})
+export const TrackTargetOpenExtension = buildMarkerExtension('open')
+export const TrackTargetCloseExtension = buildMarkerExtension('close')
diff --git a/apps/x/apps/renderer/src/styles/editor.css b/apps/x/apps/renderer/src/styles/editor.css
index 21f8956a..2083f4b0 100644
--- a/apps/x/apps/renderer/src/styles/editor.css
+++ b/apps/x/apps/renderer/src/styles/editor.css
@@ -718,39 +718,47 @@
 }
 
 /* =============================================================
-   Track Target — rendered output region below a track chip.
-   Display-only; the backend is the sole writer.
+   Track target markers — thin visual bookends around a track's
+   output region. The content BETWEEN these markers is normal,
+   editable document content (rendered by the existing extensions).
    ============================================================= */
 
-.tiptap-editor .ProseMirror .track-target-wrapper {
-  margin: 6px 0 10px 0;
-}
-
-.tiptap-editor .ProseMirror .track-target-box {
+.tiptap-editor .ProseMirror div[data-type="track-target-open"] {
   position: relative;
-  padding: 10px 12px 10px 16px;
-  border: 1px solid color-mix(in srgb, var(--foreground) 10%, transparent);
-  border-left: 3px solid color-mix(in srgb, var(--foreground) 30%, transparent);
-  border-radius: 8px;
-  background: color-mix(in srgb, var(--foreground) 3%, transparent);
-  user-select: text;
-  font-size: 13.5px;
-  line-height: 1.55;
+  height: 1px;
+  margin: 14px 0 6px 0;
+  background: color-mix(in srgb, var(--foreground) 15%, transparent);
+  pointer-events: none;
 }
 
-.tiptap-editor .ProseMirror .track-target-wrapper.ProseMirror-selectednode .track-target-box {
+.tiptap-editor .ProseMirror div[data-type="track-target-open"]::before {
+  content: 'track: ' attr(data-track-id);
+  position: absolute;
+  top: -8px;
+  left: 8px;
+  padding: 0 6px;
+  background: var(--background, #fff);
+  font-size: 10px;
+  font-weight: 500;
+  letter-spacing: 0.02em;
+  color: color-mix(in srgb, var(--foreground) 50%, transparent);
+  text-transform: none;
+  white-space: nowrap;
+  pointer-events: auto;
+}
+
+.tiptap-editor .ProseMirror div[data-type="track-target-close"] {
+  height: 1px;
+  margin: 6px 0 14px 0;
+  background: color-mix(in srgb, var(--foreground) 10%, transparent);
+  pointer-events: none;
+}
+
+.tiptap-editor .ProseMirror div[data-type="track-target-open"].ProseMirror-selectednode,
+.tiptap-editor .ProseMirror div[data-type="track-target-close"].ProseMirror-selectednode {
   outline: 2px solid color-mix(in srgb, var(--foreground) 30%, transparent);
-  outline-offset: 2px;
-}
-
-.tiptap-editor .ProseMirror .track-target-markdown > *:first-child { margin-top: 0; }
-.tiptap-editor .ProseMirror .track-target-markdown > *:last-child { margin-bottom: 0; }
-
-.tiptap-editor .ProseMirror .track-target-empty {
-  display: block;
-  font-size: 12px;
-  color: color-mix(in srgb, var(--foreground) 45%, transparent);
-  font-style: italic;
+  outline-offset: 1px;
+  pointer-events: auto;
 }
 
 /* Shared block styles (image, embed, chart, table) */