diff --git a/plugins/_editor/AGENTS.md b/plugins/_editor/AGENTS.md
index 6aa878756..8d4fabda6 100644
--- a/plugins/_editor/AGENTS.md
+++ b/plugins/_editor/AGENTS.md
@@ -20,6 +20,7 @@
 - Keep Editor Open wired through the File Browser text picker so users can open one or more Markdown or plain text files with an obvious confirmation action.
 - Keep Download in the Editor file-actions menu and save dirty text before downloading it.
 - Keep Save As distinct from Rename: Save As writes the current editor text to a chosen `.md` or `.txt` path and retargets the active session without removing the original file.
+- Keep Markdown and plain text on the same toolbar, with full-document source and preview modes plus shared Undo/Redo buttons and keyboard shortcuts.
 - Preserve source chat context ids when opening Markdown files from tool-result canvas handoffs.
 
 ## Work Guidance
diff --git a/plugins/_editor/webui/editor-panel.html b/plugins/_editor/webui/editor-panel.html
index 4abb20e2f..fcf18713d 100644
--- a/plugins/_editor/webui/editor-panel.html
+++ b/plugins/_editor/webui/editor-panel.html
@@ -8,7 +8,7 @@
   <div x-data>
     <template x-if="$store.editor">
       <div class="editor-panel" x-create="$store.editor.onMount($el, xAttrs($el) || {})" x-destroy="$store.editor.cleanup()">
-        <div class="editor-shell" @keydown="$store.editor.handleEditorKeydown($event)">
+        <div class="editor-shell" @keydown.capture="$store.editor.handleEditorKeydown($event)">
           <div class="editor-tabs" x-show="$store.editor.visibleTabs().length > 0" style="display: none;" role="tablist" aria-label="Open text files">
             <template x-for="tab in $store.editor.visibleTabs()" :key="tab.tab_id">
               <div
@@ -82,7 +82,7 @@
               <button
                 type="button"
                 class="editor-icon-button editor-mode-toggle"
-                x-show="$store.editor.isMarkdown()"
+                x-show="$store.editor.isTextDocument()"
                 style="display: none;"
                 :title="$store.editor.viewModeTitle()"
                 :aria-label="$store.editor.viewModeTitle()"
@@ -91,44 +91,40 @@
                 <span class="material-symbols-outlined" aria-hidden="true" x-text="$store.editor.viewModeIcon()"></span>
               </button>
 
-              <div class="editor-tool-group editor-source-tools" x-show="$store.editor.isTextDocument() && $store.editor.isSourceMode()" style="display: none;">
-                <button type="button" class="editor-icon-button" title="Undo" aria-label="Undo" :disabled="!$store.editor.canUndo()" @click="$store.editor.undo()">
+              <div class="editor-tool-group editor-history-tools" x-show="$store.editor.isTextDocument()" style="display: none;">
+                <button type="button" class="editor-icon-button" title="Undo" aria-label="Undo" :disabled="$store.editor.previewEditing || !$store.editor.canUndo()" @click="$store.editor.undo()">
                   <span class="material-symbols-outlined">undo</span>
                 </button>
-                <button type="button" class="editor-icon-button" title="Redo" aria-label="Redo" :disabled="!$store.editor.canRedo()" @click="$store.editor.redo()">
+                <button type="button" class="editor-icon-button" title="Redo" aria-label="Redo" :disabled="$store.editor.previewEditing || !$store.editor.canRedo()" @click="$store.editor.redo()">
                   <span class="material-symbols-outlined">redo</span>
                 </button>
-                <button type="button" class="editor-icon-button" title="Bold" aria-label="Bold" x-show="$store.editor.isMarkdown()" @click="$store.editor.format('bold')">
+              </div>
+
+              <div class="editor-tool-group editor-source-tools" x-show="$store.editor.isTextDocument() && $store.editor.isSourceMode()" style="display: none;">
+                <button type="button" class="editor-icon-button" title="Bold" aria-label="Bold" @click="$store.editor.format('bold')">
                   <span class="material-symbols-outlined">format_bold</span>
                 </button>
-                <button type="button" class="editor-icon-button" title="Italic" aria-label="Italic" x-show="$store.editor.isMarkdown()" @click="$store.editor.format('italic')">
+                <button type="button" class="editor-icon-button" title="Italic" aria-label="Italic" @click="$store.editor.format('italic')">
                   <span class="material-symbols-outlined">format_italic</span>
                 </button>
-                <button type="button" class="editor-icon-button" title="List" aria-label="List" x-show="$store.editor.isMarkdown()" @click="$store.editor.format('list')">
+                <button type="button" class="editor-icon-button" title="List" aria-label="List" @click="$store.editor.format('list')">
                   <span class="material-symbols-outlined">format_list_bulleted</span>
                 </button>
-                <button type="button" class="editor-icon-button" title="Numbered list" aria-label="Numbered list" x-show="$store.editor.isMarkdown()" @click="$store.editor.format('numbered')">
+                <button type="button" class="editor-icon-button" title="Numbered list" aria-label="Numbered list" @click="$store.editor.format('numbered')">
                   <span class="material-symbols-outlined">format_list_numbered</span>
                 </button>
-                <button type="button" class="editor-icon-button" title="Table" aria-label="Table" x-show="$store.editor.isMarkdown()" @click="$store.editor.format('table')">
+                <button type="button" class="editor-icon-button" title="Table" aria-label="Table" @click="$store.editor.format('table')">
                   <span class="material-symbols-outlined">table</span>
                 </button>
               </div>
-              <div class="editor-tool-group editor-preview-tools" x-show="$store.editor.isMarkdown() && $store.editor.isPreviewMode()" style="display: none;">
-                <button type="button" class="editor-icon-button" title="Previous page" aria-label="Previous page" :disabled="$store.editor.previewEditing || $store.editor.activePageIndex <= 0" @click="$store.editor.previousPage()">
-                  <span class="material-symbols-outlined">chevron_left</span>
-                </button>
-                <span class="editor-page-count" x-text="$store.editor.pagePositionLabel()"></span>
-                <button type="button" class="editor-icon-button" title="Next page" aria-label="Next page" :disabled="$store.editor.previewEditing || $store.editor.activePageIndex >= $store.editor.pages().length - 1" @click="$store.editor.nextPage()">
-                  <span class="material-symbols-outlined">chevron_right</span>
-                </button>
-                <button type="button" class="editor-icon-button" title="Edit page" aria-label="Edit page" x-show="!$store.editor.previewEditing" @click="$store.editor.startPreviewEdit()">
+              <div class="editor-tool-group editor-preview-tools" x-show="$store.editor.isTextDocument() && $store.editor.isPreviewMode()" style="display: none;">
+                <button type="button" class="editor-icon-button" title="Edit document" aria-label="Edit document" x-show="!$store.editor.previewEditing" @click="$store.editor.startPreviewEdit()">
                   <span class="material-symbols-outlined">edit_note</span>
                 </button>
-                <button type="button" class="editor-icon-button is-primary" title="Apply page edit" aria-label="Apply page edit" x-show="$store.editor.previewEditing" @click="$store.editor.applyPreviewEdit()">
+                <button type="button" class="editor-icon-button is-primary" title="Apply document edit" aria-label="Apply document edit" x-show="$store.editor.previewEditing" @click="$store.editor.applyPreviewEdit()">
                   <span class="material-symbols-outlined">check</span>
                 </button>
-                <button type="button" class="editor-icon-button" title="Cancel page edit" aria-label="Cancel page edit" x-show="$store.editor.previewEditing" @click="$store.editor.cancelPreviewEdit()">
+                <button type="button" class="editor-icon-button" title="Cancel document edit" aria-label="Cancel document edit" x-show="$store.editor.previewEditing" @click="$store.editor.cancelPreviewEdit()">
                   <span class="material-symbols-outlined">close</span>
                 </button>
                 <button type="button" class="editor-icon-button" title="Search" aria-label="Search" :disabled="$store.editor.previewEditing" @click="$store.editor.openSearch()">
@@ -241,7 +237,7 @@
               </div>
             </div>
 
-            <div class="editor-preview-shell" x-show="$store.editor.session && $store.editor.isMarkdown() && $store.editor.isPreviewMode()" style="display: none;">
+            <div class="editor-preview-shell" x-show="$store.editor.session && $store.editor.isTextDocument() && $store.editor.isPreviewMode()" style="display: none;">
               <div class="editor-preview-title">
                 <h1 x-text="$store.editor.pageTitle()"></h1>
               </div>
@@ -249,7 +245,7 @@
                 <textarea
                   class="editor-preview-page-editor"
                   data-editor-preview-source
-                  aria-label="Markdown page source"
+                  aria-label="Document source"
                   x-model="$store.editor.previewEditText"
                   @input="$store.editor.onPreviewEditInput()"
                   @keydown.meta.enter.prevent="$store.editor.applyPreviewEdit()"
@@ -263,7 +259,7 @@
                 data-editor-preview
                 x-show="!$store.editor.previewEditing"
                 x-html="$store.editor.previewHtml()"
-                x-effect="$store.editor.activePageIndex; $store.editor.editorText; $store.editor.searchQuery; $store.editor.searchIndex; $store.editor.schedulePreviewEnhance()"
+                x-effect="$store.editor.editorText; $store.editor.searchQuery; $store.editor.searchIndex; $store.editor.schedulePreviewEnhance()"
                 @click="$store.editor.handlePreviewClick($event)"
               ></div>
             </div>
@@ -597,7 +593,6 @@
       min-width: 8px;
     }
 
-    .editor-page-count,
     .editor-search-count {
       min-width: 54px;
       color: var(--color-text-secondary);
diff --git a/plugins/_editor/webui/editor-preview.js b/plugins/_editor/webui/editor-preview.js
index 47fcc8cfb..767fdb2a6 100644
--- a/plugins/_editor/webui/editor-preview.js
+++ b/plugins/_editor/webui/editor-preview.js
@@ -1,6 +1,5 @@
 import { renderSafeMarkdown } from "/js/safe-markdown.js";
 
-const PAGE_HEADING_RE = /^(#{1,2})\s+(.+?)\s*#*\s*$/;
 const FOOTNOTE_DEF_RE = /^\[\^([^\]]+)\]:\s*(.*)$/;
 
 export function renderEditorPreviewMarkdown(markdown = "", fullMarkdown = markdown) {
@@ -13,68 +12,15 @@ export function renderEditorPreviewMarkdown(markdown = "", fullMarkdown = markdo
 
 export function buildMarkdownPages(markdown = "", fallbackTitle = "Markdown") {
   const source = String(markdown || "");
-  const lines = source.split("\n");
-  const pages = [];
-  let current = null;
-  let intro = [];
-  let introStart = 0;
-  let fenced = false;
-  let offset = 0;
-
-  const startPage = (title, level, line, start) => {
-    if (current) {
-      current.end = start;
-      pages.push(finalizePage(current, pages.length, source));
-    }
-    current = {
-      title: cleanHeadingText(title) || fallbackTitle,
-      level,
-      lines: [line],
-      start,
-      end: source.length,
-    };
-  };
-
-  for (const [index, line] of lines.entries()) {
-    const lineStart = offset;
-    const lineEnd = lineStart + line.length + (index < lines.length - 1 ? 1 : 0);
-    if (/^\s*```/.test(line)) fenced = !fenced;
-    const match = !fenced ? line.match(PAGE_HEADING_RE) : null;
-    if (match) {
-      if (!current && intro.join("\n").trim()) {
-        pages.push(finalizePage({
-          title: fallbackTitle,
-          level: 0,
-          lines: intro,
-          start: introStart,
-          end: lineStart,
-        }, pages.length, source));
-        intro = [];
-      }
-      startPage(match[2], match[1].length, line, lineStart);
-      offset = lineEnd;
-      continue;
-    }
-    if (current) current.lines.push(line);
-    else intro.push(line);
-    offset = lineEnd;
-  }
-
-  if (current) {
-    current.end = source.length;
-    pages.push(finalizePage(current, pages.length, source));
-  }
-  else if (intro.join("\n").trim() || !pages.length) {
-    pages.push(finalizePage({
-      title: fallbackTitle,
-      level: 0,
-      lines: intro,
-      start: introStart,
-      end: source.length,
-    }, pages.length, source));
-  }
-
-  return pages;
+  return [{
+    index: 0,
+    title: fallbackTitle,
+    level: 0,
+    anchor: slugifyHeading(fallbackTitle),
+    start: 0,
+    end: source.length,
+    markdown: source,
+  }];
 }
 
 export function slugifyHeading(text = "", used = new Map()) {
@@ -119,28 +65,6 @@ export function isMarkdownPath(path = "") {
   return /\.md(?:own)?$/i.test(String(path || "").split(/[?#]/, 1)[0]);
 }
 
-function finalizePage(page, index, source = "") {
-  const start = Math.max(0, Number(page.start || 0));
-  const end = Math.max(start, Number(page.end ?? String(source || "").length));
-  const markdown = String(source || "").slice(start, end) || page.lines.join("\n");
-  return {
-    index,
-    title: page.title,
-    level: page.level,
-    anchor: slugifyHeading(page.title),
-    start,
-    end,
-    markdown,
-  };
-}
-
-function cleanHeadingText(text = "") {
-  return String(text || "")
-    .replace(/\\([\\`*_[\]{}()#+.!-])/g, "$1")
-    .replace(/[*_`~]/g, "")
-    .trim();
-}
-
 function prepareFootnotes(markdown = "", fullMarkdown = markdown) {
   const definitions = [];
   const body = [];
diff --git a/plugins/_editor/webui/editor-store.js b/plugins/_editor/webui/editor-store.js
index 7a11c5ead..7c8ba8d9c 100644
--- a/plugins/_editor/webui/editor-store.js
+++ b/plugins/_editor/webui/editor-store.js
@@ -251,6 +251,7 @@ const model = {
   _inputTimer: null,
   _history: [],
   _historyIndex: -1,
+  _historyPushedAt: 0,
   _pendingFocus: false,
   _pendingFocusEnd: true,
   _focusAttempts: 0,
@@ -336,7 +337,7 @@ const model = {
   },
 
   async setViewMode(mode) {
-    const next = mode === PREVIEW_MODE && this.isMarkdown() ? PREVIEW_MODE : SOURCE_MODE;
+    const next = mode === PREVIEW_MODE && this.isTextDocument() ? PREVIEW_MODE : SOURCE_MODE;
     if (this.viewMode === next) return;
     this.applyPreviewEdit({ silent: true });
     this.syncEditorText();
@@ -354,7 +355,7 @@ const model = {
   },
 
   async toggleViewMode() {
-    if (!this.isMarkdown()) return;
+    if (!this.isTextDocument()) return;
     await this.setViewMode(this.isPreviewMode() ? SOURCE_MODE : PREVIEW_MODE);
   },
 
@@ -367,7 +368,7 @@ const model = {
   },
 
   pages() {
-    if (!this.isMarkdown()) return [];
+    if (!this.isTextDocument()) return [];
     return buildMarkdownPages(this.editorText, this.tabTitle(this.session || {}));
   },
 
@@ -381,35 +382,13 @@ const model = {
     return this.currentPage().title || this.tabTitle(this.session || {});
   },
 
-  pagePositionLabel() {
-    const pages = this.pages();
-    if (!pages.length) return "";
-    return `${Math.min(this.activePageIndex + 1, pages.length)} of ${pages.length}`;
-  },
-
   previewHtml() {
-    if (!this.isMarkdown()) return "";
+    if (!this.isTextDocument()) return "";
     return renderEditorPreviewMarkdown(this.currentPage().markdown || "", this.editorText);
   },
 
-  selectPage(index) {
-    if (this.previewEditing) return;
-    const pages = this.pages();
-    if (!pages.length) return;
-    this.activePageIndex = Math.max(0, Math.min(Number(index) || 0, pages.length - 1));
-    this.schedulePreviewEnhance();
-  },
-
-  nextPage() {
-    this.selectPage(this.activePageIndex + 1);
-  },
-
-  previousPage() {
-    this.selectPage(this.activePageIndex - 1);
-  },
-
   startPreviewEdit() {
-    if (!this.session || !this.isMarkdown() || !this.isPreviewMode()) return;
+    if (!this.session || !this.isTextDocument() || !this.isPreviewMode()) return;
     const page = this.currentPage();
     this.previewEditing = true;
     this.previewEditDirty = false;
@@ -457,7 +436,7 @@ const model = {
     this.previewEditPageIndex = -1;
 
     return this.replacePageMarkdown(page, replacement, {
-      message: "Page updated",
+      message: "Document updated",
       silent: options.silent,
     });
   },
@@ -493,7 +472,7 @@ const model = {
   },
 
   togglePreviewTask(taskIndex, checked) {
-    if (!this.session || !this.isMarkdown() || !this.isPreviewMode() || this.previewEditing) return false;
+    if (!this.session || !this.isTextDocument() || !this.isPreviewMode() || this.previewEditing) return false;
     const page = this.currentPage();
     const lines = String(page.markdown || "").split("\n");
     const indexes = taskLineIndexes(page.markdown || "");
@@ -514,7 +493,7 @@ const model = {
   },
 
   schedulePreviewEnhance() {
-    if (!this.isMarkdown() || !this.isPreviewMode()) return;
+    if (!this.isTextDocument() || !this.isPreviewMode()) return;
     if (this._previewEnhanceTimer) globalThis.clearTimeout(this._previewEnhanceTimer);
     this._previewEnhanceTimer = globalThis.setTimeout(() => {
       this._previewEnhanceTimer = null;
@@ -707,7 +686,7 @@ const model = {
   },
 
   openSearch() {
-    if (!this.isMarkdown()) return;
+    if (!this.isTextDocument()) return;
     if (!this.isPreviewMode()) {
       this.setViewMode(PREVIEW_MODE);
     }
@@ -870,8 +849,19 @@ const model = {
   },
 
   handleEditorKeydown(event) {
-    if ((event.metaKey || event.ctrlKey) && event.key.toLowerCase() === "f") {
-      if (!this.isMarkdown()) return;
+    if (!(event.metaKey || event.ctrlKey) || !this.isTextDocument()) return;
+    const key = event.key.toLowerCase();
+    const historyAction = key === "y" || (key === "z" && event.shiftKey) ? "redo" : key === "z" ? "undo" : "";
+    const nativeEditing = event.target?.matches?.("input, textarea, [contenteditable='true']")
+      && !event.target.closest?.("[data-editor-ace], [data-editor-source]");
+    if (nativeEditing) return;
+    if (historyAction && !this.previewEditing) {
+      event.preventDefault();
+      event.stopPropagation();
+      this[historyAction]();
+      return;
+    }
+    if (key === "f") {
       event.preventDefault();
       this.openSearch();
     }
@@ -982,11 +972,6 @@ const model = {
     this.activeTabId = tab?.tab_id || "";
     this.editorText = String(tab?.text || "");
     this.dirty = Boolean(tab?.dirty);
-    if (!this.isMarkdown(tab) && this.isPreviewMode()) {
-      this.viewMode = SOURCE_MODE;
-      this.searchOpen = false;
-      this.searchQuery = "";
-    }
     if (this.previewEditing) this.cancelPreviewEdit();
     if (!options.preservePage) {
       this.activePageIndex = 0;
@@ -1500,7 +1485,6 @@ const model = {
     const wasActive = this.activeTabId === (previous?.tab_id || next.tab_id);
     if (wasActive) {
       this.session = next;
-      if (!this.isMarkdown(next) && this.isPreviewMode()) this.viewMode = SOURCE_MODE;
       this.updateSourceEditorMode(next);
     }
     const index = this.tabs.findIndex((tab) => tab.tab_id === (previous?.tab_id || next.tab_id));
@@ -1519,37 +1503,41 @@ const model = {
   resetHistory(text) {
     this._history = [String(text || "")];
     this._historyIndex = 0;
+    this._historyPushedAt = 0;
   },
 
-  pushHistory(text) {
+  pushHistory(text, coalesce = false) {
     const value = String(text || "");
     if (this._history[this._historyIndex] === value) return;
+    const now = Date.now();
+    if (
+      coalesce
+      && this._historyPushedAt
+      && now - this._historyPushedAt <= INPUT_PUSH_DELAY_MS
+      && this._historyIndex === this._history.length - 1
+      && this._historyIndex > 0
+    ) {
+      this._history[this._historyIndex] = value;
+      this._historyPushedAt = now;
+      return;
+    }
     this._history = this._history.slice(0, this._historyIndex + 1);
     this._history.push(value);
     if (this._history.length > MAX_HISTORY) this._history.shift();
     this._historyIndex = this._history.length - 1;
+    this._historyPushedAt = coalesce ? now : 0;
   },
 
   undo() {
-    if (this.sourceEditor && this.isSourceMode()) {
-      this.sourceEditor.undo();
-      this.editorText = this.sourceEditor.getValue();
-      this.syncEditorText();
-      return;
-    }
     if (this._historyIndex <= 0) return;
+    this._historyPushedAt = 0;
     this._historyIndex -= 1;
     this.applyEditorText(this._history[this._historyIndex], true);
   },
 
   redo() {
-    if (this.sourceEditor && this.isSourceMode()) {
-      this.sourceEditor.redo();
-      this.editorText = this.sourceEditor.getValue();
-      this.syncEditorText();
-      return;
-    }
     if (this._historyIndex >= this._history.length - 1) return;
+    this._historyPushedAt = 0;
     this._historyIndex += 1;
     this.applyEditorText(this._history[this._historyIndex], true);
   },
@@ -1580,7 +1568,7 @@ const model = {
 
   onSourceInput() {
     this.markDirty();
-    this.pushHistory(this.editorText);
+    this.pushHistory(this.editorText, true);
     this.scheduleInputPush();
   },
 
@@ -1613,7 +1601,7 @@ const model = {
   },
 
   format(command) {
-    if (!this.session || !this.isMarkdown()) return;
+    if (!this.session || !this.isTextDocument()) return;
     if (this.sourceEditor && this.isSourceMode()) {
       const selected = this.sourceEditor.getSelectedText();
       const replacement = this.formatReplacement(command, selected);
diff --git a/tests/test_office_canvas_setup.py b/tests/test_office_canvas_setup.py
index b3af5c73c..d3bd57da1 100644
--- a/tests/test_office_canvas_setup.py
+++ b/tests/test_office_canvas_setup.py
@@ -156,6 +156,8 @@ def test_right_canvas_uses_desktop_surface_id_and_migrates_legacy_office_state()
     assert 'input[type="checkbox"]' in editor_store
     assert "renderEditorPreviewMarkdown" in editor_store
     assert "buildMarkdownPages" in editor_store
+    assert "PAGE_HEADING_RE" not in editor_preview
+    assert "markdown: source" in editor_preview
     assert "hydrateActiveSession" in editor_store
     assert "refreshSourceEditorLayout" in editor_store
     assert "editor.resize?.(true)" in editor_store
@@ -170,7 +172,6 @@ def test_right_canvas_uses_desktop_surface_id_and_migrates_legacy_office_state()
     assert "renderSafeMarkdown" in editor_preview
     assert "prepareFootnotes" in editor_preview
     assert "resolveDocumentRelativePath" in editor_preview
-    assert "slice(start, end)" in editor_preview
     assert "allowDataImages: true" in editor_preview
     assert "allowLatex: true" in editor_preview
     assert "html = sanitizeHtml(html, options);" in safe_markdown
@@ -564,6 +565,7 @@ def test_editor_toolbar_places_preview_toggle_left_and_save_on_right():
     toolbar = editor_panel[toolbar_start:toolbar_end]
 
     mode_toggle = toolbar.index("editor-mode-toggle")
+    history_tools = toolbar.index("editor-history-tools")
     source_tools = toolbar.index("editor-source-tools")
     preview_tools = toolbar.index("editor-preview-tools")
     spacer = toolbar.index("editor-toolbar-spacer")
@@ -572,8 +574,8 @@ def test_editor_toolbar_places_preview_toggle_left_and_save_on_right():
     file_actions = toolbar.index("editor-file-actions")
     file_menu = toolbar.index("editor-file-menu")
 
-    assert mode_toggle < source_tools
-    assert mode_toggle < preview_tools
+    assert mode_toggle < history_tools < source_tools
+    assert history_tools < preview_tools
     assert spacer < save_button < save_as_button < file_actions < file_menu
     assert "@click=\"$store.editor.save()\"" in toolbar
     assert "@click=\"$store.editor.saveAs()\"" in toolbar
@@ -589,6 +591,61 @@ def test_editor_toolbar_places_preview_toggle_left_and_save_on_right():
     assert "<span>Close File</span>" in file_menu_markup
 
 
+def test_editor_uses_full_document_preview_and_matching_markdown_text_tools():
+    editor_panel = read("plugins", "_editor", "webui", "editor-panel.html")
+    editor_store = read("plugins", "_editor", "webui", "editor-store.js")
+
+    assert "Previous page" not in editor_panel
+    assert "Next page" not in editor_panel
+    assert "editor-page-count" not in editor_panel
+    assert "pagePositionLabel" not in editor_store
+    assert "nextPage()" not in editor_store
+    assert "previousPage()" not in editor_store
+    assert 'x-show="$store.editor.isTextDocument()"' in editor_panel
+    assert '$store.editor.isTextDocument() && $store.editor.isPreviewMode()' in editor_panel
+    assert 'mode === PREVIEW_MODE && this.isTextDocument()' in editor_store
+    assert "if (!this.session || !this.isTextDocument()) return;" in editor_store
+
+    source_tools_start = editor_panel.index('class="editor-tool-group editor-source-tools"')
+    preview_tools_start = editor_panel.index('class="editor-tool-group editor-preview-tools"')
+    source_tools = editor_panel[source_tools_start:preview_tools_start]
+    for action in ("Bold", "Italic", "List", "Numbered list", "Table"):
+        assert f'title="{action}"' in source_tools
+    assert "isMarkdown()" not in source_tools
+
+
+def test_editor_history_shortcuts_and_toolbar_controls_cover_markdown_and_text():
+    editor_panel = read("plugins", "_editor", "webui", "editor-panel.html")
+    editor_store = read("plugins", "_editor", "webui", "editor-store.js")
+
+    assert '@keydown.capture="$store.editor.handleEditorKeydown($event)"' in editor_panel
+    history_start = editor_panel.index('class="editor-tool-group editor-history-tools"')
+    source_start = editor_panel.index('class="editor-tool-group editor-source-tools"')
+    history_tools = editor_panel[history_start:source_start]
+    assert 'x-show="$store.editor.isTextDocument()"' in history_tools
+    assert 'title="Undo"' in history_tools
+    assert 'title="Redo"' in history_tools
+    assert "$store.editor.previewEditing || !$store.editor.canUndo()" in history_tools
+    assert "$store.editor.previewEditing || !$store.editor.canRedo()" in history_tools
+
+    keydown_start = editor_store.index("handleEditorKeydown(event)")
+    create_start = editor_store.index("\n  async create", keydown_start)
+    keydown = editor_store[keydown_start:create_start]
+    assert 'key === "z"' in keydown
+    assert 'key === "y"' in keydown
+    assert "event.stopPropagation()" in keydown
+    assert "this[historyAction]()" in keydown
+    assert "nativeEditing" in keydown
+
+    undo_start = editor_store.index("\n  undo()")
+    can_undo_start = editor_store.index("\n  canUndo()", undo_start)
+    history_actions = editor_store[undo_start:can_undo_start]
+    assert "sourceEditor.undo" not in history_actions
+    assert "sourceEditor.redo" not in history_actions
+    assert "pushHistory(text, coalesce = false)" in editor_store
+    assert "this.pushHistory(this.editorText, true)" in editor_store
+
+
 def test_desktop_text_open_with_routes_to_editor_surface():
     desktop_session = read("plugins", "_desktop", "helpers", "desktop_session.py")
     desktop_store = read("plugins", "_desktop", "webui", "desktop-store.js")