diff --git a/apps/web/src/components/sandbox/blocks/blocks-panel.tsx b/apps/web/src/components/sandbox/blocks/blocks-panel.tsx
index a09336a597..dce375cbcf 100644
--- a/apps/web/src/components/sandbox/blocks/blocks-panel.tsx
+++ b/apps/web/src/components/sandbox/blocks/blocks-panel.tsx
@@ -22,7 +22,12 @@ import {
   BlocksEmptyState,
   BlocksErrorState,
 } from "@/layouts/main-panel-tabs/blocks-tab-states";
+import { useContentBackend } from "@/components/sections-editor/use-content-backend";
+import { isProtocolProject } from "@/components/sections-editor/content-backend";
 import { PanelLoading } from "@/layouts/main-panel-boundary";
+import { isNoSchemaMeta } from "@/components/sections-editor/schemaless";
+import { SchemalessEditor } from "@/components/sandbox/content/schemaless-editor";
+import { useNewBlocksEditorState } from "@/hooks/use-new-blocks-editor";
 
 const SectionsEditor = lazy(() =>
   import("@/components/sections-editor/sections-editor").then((m) => ({
@@ -67,6 +72,7 @@ export function BlocksPanel({
         previewUrl,
       }
     : null;
+  const contentBackend = useContentBackend(virtualMcpId, currentBranch);
   const decofile = useDecofile(fetchParams, { fetchEnabled: devServerReady });
   const meta = useLiveMeta(fetchParams, { fetchEnabled: devServerReady });
   const state = resolveBlocksTabState({
@@ -74,16 +80,41 @@ export function BlocksPanel({
     decofile: toBlocksQueryState(decofile),
     meta: toBlocksQueryState(meta),
     hasEditableContent: hasEditableDecoContent(decofile.data, meta.data),
-    fastPreviewActive: useSessionRuntime(virtualMcpId).runtime === "cms",
+    fastPreviewActive:
+      useSessionRuntime(virtualMcpId).runtime === "cms" ||
+      isProtocolProject(contentBackend),
   });
 
+  // Which editor this site gets (v8: the new one) waits on the same
+  // detection, so neither editor shows and then swaps to the other.
+  const editorUndecided = useNewBlocksEditorState() === undefined;
+
   const panel = (children: ReactNode) => (
     <div data-testid="blocks-panel" className="h-full min-h-0 overflow-hidden">
       {children}
     </div>
   );
 
-  if (state.kind === "loading") return panel(<PanelLoading />);
+  if (state.kind === "loading" || editorUndecided) {
+    return panel(<PanelLoading />);
+  }
+  // No schema yet: the page (or any block) as plain fields, never an error.
+  if (decofile.data && isNoSchemaMeta(meta.data)) {
+    const target = workspace.state.target;
+    const initialKey =
+      target?.kind === "page" || target?.kind === "section" ? target.key : null;
+    return panel(
+      <SchemalessEditor
+        key={initialKey ?? ""}
+        orgSlug={org.slug}
+        virtualMcpId={virtualMcpId}
+        branch={currentBranch ?? ""}
+        decofile={decofile.data}
+        initialKey={initialKey}
+        compact
+      />,
+    );
+  }
   if (state.kind === "empty") return panel(<BlocksEmptyState />);
   if (state.kind === "error") {
     const retry = () => {
diff --git a/apps/web/src/components/sandbox/content/app-editor.tsx b/apps/web/src/components/sandbox/content/app-editor.tsx
index 13f4e3be63..ee0ea98d17 100644
--- a/apps/web/src/components/sandbox/content/app-editor.tsx
+++ b/apps/web/src/components/sandbox/content/app-editor.tsx
@@ -1,7 +1,7 @@
 import { useOptionalChatTask } from "@/components/chat/chat-context";
 import { Spinner } from "@decocms/ui/components/spinner.tsx";
 import { ChevronRight } from "@untitledui/icons";
-import { useRef, useState } from "react";
+import { type ReactNode, useRef, useState } from "react";
 import { toast } from "sonner";
 import { cn } from "@decocms/ui/lib/utils.ts";
 import { ScrollArea } from "@decocms/ui/components/scroll-area.tsx";
@@ -12,6 +12,7 @@ import type { LiveMeta } from "@/components/sections-editor/resolve-schema";
 import type { SectionCatalogEntry } from "@/components/sections-editor/section-catalog";
 import { createReferencedBlockSaver } from "@/components/sections-editor/save-referenced-block";
 import {
+  type SaveGuard,
   useDebouncedSaveBlock,
   useSaveBlock,
 } from "@/components/sections-editor/use-save-block";
@@ -38,6 +39,8 @@ export function AppEditor({
   excludeFields,
   schemaPending = false,
   previewBaseUrl = null,
+  notice,
+  saveGuard,
 }: {
   orgSlug: string;
   virtualMcpId: string;
@@ -51,6 +54,10 @@ export function AppEditor({
   excludeFields?: readonly string[];
   schemaPending?: boolean;
   previewBaseUrl?: string | null;
+  /** Shown above the form (e.g. that the block is not saved yet). */
+  notice?: ReactNode;
+  /** A version guard for this block's autosaves (e.g. create-only on the first save). */
+  saveGuard?: SaveGuard;
 }) {
   const threadId = useOptionalChatTask()?.taskId ?? null;
   const t = useT();
@@ -58,6 +65,7 @@ export function AppEditor({
   // back to the Fast Preview production deployment while the sandbox boots.
   const sectionPreviewBase = useSectionPreviewBase({
     virtualMcpId,
+    branch,
     sandboxUrl: previewBaseUrl,
   });
   const resolveType =
@@ -68,11 +76,10 @@ export function AppEditor({
   const title =
     titleOverride ?? (block ? appLabel(blockKey, block, meta) : blockKey);
 
-  const { save, flush, isPending } = useDebouncedSaveBlock({
-    orgSlug,
-    virtualMcpId,
-    branch,
-  });
+  const { save, flush, isPending } = useDebouncedSaveBlock(
+    { orgSlug, virtualMcpId, branch },
+    { guard: saveGuard },
+  );
   const saveBlock = useSaveBlock({ orgSlug, virtualMcpId, branch });
   const saveReferencedBlock = createReferencedBlockSaver((refKey, data) =>
     save(refKey, data),
@@ -212,6 +219,7 @@ export function AppEditor({
       <ScrollArea className="min-h-0 min-w-0 flex-1 [&_[data-slot=scroll-area-viewport]>div]:!block">
         <div className="px-6 py-6">
           <div className="mx-auto max-w-xl">
+            {notice}
             {hasEditableFields ? (
               <SchemaForm
                 key={`${blockKey}:${formResetKey}`}
diff --git a/apps/web/src/components/sandbox/content/schemaless-editor.tsx b/apps/web/src/components/sandbox/content/schemaless-editor.tsx
new file mode 100644
index 0000000000..a319162cd7
--- /dev/null
+++ b/apps/web/src/components/sandbox/content/schemaless-editor.tsx
@@ -0,0 +1,45 @@
+import { useEffect, useEffectEvent } from "react";
+import { useDebouncedSaveBlock } from "@/components/sections-editor/use-save-block";
+import { SchemalessContent } from "./schemaless-content";
+
+/**
+ * `SchemalessContent` wired to the editor's autosave (debounced, one
+ * `blocks.apply` per block). Pending edits are saved on leaving a block and
+ * when this unmounts, which is what happens the moment the schema appears
+ * and the regular editor takes over.
+ */
+export function SchemalessEditor({
+  orgSlug,
+  virtualMcpId,
+  branch,
+  decofile,
+  initialKey,
+  compact,
+}: {
+  orgSlug: string;
+  virtualMcpId: string;
+  branch: string;
+  decofile: Record<string, unknown>;
+  initialKey?: string | null;
+  compact?: boolean;
+}) {
+  const { save, flush } = useDebouncedSaveBlock({
+    orgSlug,
+    virtualMcpId,
+    branch,
+  });
+  // Saves what's pending when the editor goes away (the debounce alone
+  // would drop it): runs after the save hook's own timer cleanup.
+  const flushPending = useEffectEvent(() => flush());
+  // oxlint-disable-next-line ban-use-effect/ban-use-effect -- flush pending autosaves on unmount
+  useEffect(() => () => flushPending(), []);
+  return (
+    <SchemalessContent
+      decofile={decofile}
+      onChange={(blockKey, next) => save(blockKey, next)}
+      onLeaveBlock={flush}
+      initialKey={initialKey}
+      compact={compact}
+    />
+  );
+}
diff --git a/apps/web/src/components/sandbox/preview/preview.tsx b/apps/web/src/components/sandbox/preview/preview.tsx
index d6c793e05a..384e2daa34 100644
--- a/apps/web/src/components/sandbox/preview/preview.tsx
+++ b/apps/web/src/components/sandbox/preview/preview.tsx
@@ -21,7 +21,7 @@ import {
 import { Button } from "@decocms/ui/components/button.tsx";
 import { useState, useRef, useEffect } from "react";
 import { Spinner } from "@decocms/ui/components/spinner.tsx";
-import { useChatTask } from "@/components/chat/context";
+import { useChatTask, useOptionalChatStream } from "@/components/chat/context";
 import { useProjectContext } from "@/sdk";
 import { useSandboxLifecycle } from "@/components/sandbox/hooks/sandbox-lifecycle-context";
 import { useVirtualMCPNonBlocking } from "@/sdk";
@@ -54,8 +54,16 @@ import {
 } from "@decocms/ui/components/tooltip.tsx";
 import { ToolbarIconButton } from "@/components/toolbar-icon-button";
 import { Panel } from "@/components/panel";
-import { useDecofile } from "@/components/sections-editor/use-decofile";
+import {
+  useDecofile,
+  useDecofileCacheKey,
+} from "@/components/sections-editor/use-decofile";
 import { withVariantMatcherOverride } from "@/components/sections-editor/variant-matcher-override";
+import {
+  buildServeDraftPointer,
+  withForcedVariantsInDraftUrl,
+} from "@/components/sections-editor/variant-draft-pointer";
+import { useDecoServeConnection } from "@/hooks/use-deco-serve-connection";
 import { useLiveMeta } from "@/components/sections-editor/use-live-meta";
 import {
   extractGlobalSections,
@@ -118,7 +126,7 @@ import {
 } from "./path-param-picker-chip";
 import { PathParamInput } from "./path-param-input";
 import { buildPreviewLabel } from "./preview-label";
-import { showCmsPageSelector } from "./cms-controls";
+import { showCmsPageSelector, showPreviewToolbarFor } from "./cms-controls";
 import { useCreatePage } from "@/components/sections-editor/use-create-page";
 import { CreatePageModal } from "@/components/sections-editor/create-page-modal";
 import { sleep } from "@decocms/shared/std";
@@ -147,6 +155,12 @@ import {
   toggleVisualEditingMode,
   type PreviewEditingMode,
 } from "./editing-mode";
+import {
+  isProtocolProject,
+  servePreviewUrl,
+} from "@/components/sections-editor/content-backend";
+import { useContentBackend } from "@/components/sections-editor/use-content-backend";
+import { useContentRevision } from "@/components/sections-editor/content-protocol-api";
 import { isContentEditingEnabled } from "@/layouts/main-panel-tabs/content-editing-gate";
 import { type PreviewDeviceSize, withDeviceHint } from "./device-hint";
 
@@ -339,6 +353,11 @@ function reloadIframeOrFallback(
   }
 }
 
+/** How long after a `deco serve` save the frame may take to reload itself
+ *  before the editor reloads it: a dev server that reloads pages on content
+ *  changes does so within a few hundred ms of the save. */
+const SERVE_SELF_RELOAD_WAIT_MS = 1500;
+
 export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
   const t = useT();
   const isDesktopApp = useIsDesktopApp();
@@ -349,6 +368,9 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
     taskId: activeTaskId,
     virtualMcpId: sessionAgentId,
   } = useChatTask();
+  /** Visual editing asks the chat about a clicked element: none without one
+   *  (the account-less `/site-editor`). */
+  const hasChat = !!useOptionalChatStream();
   const workspace = useBlocksPreviewWorkspace();
   const agent = useVirtualMCPNonBlocking(
     sessionAgentId === virtualMcpId ? virtualMcpId : null,
@@ -467,7 +489,16 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
    * iframe, and the editor bridge all target it — and the boot gating is
    * bypassed (the tunnel is already up), so no pod ever boots.
    */
-  const { url: localPreviewUrl } = useLocalPreviewUrl(virtualMcpId);
+  const { url: tunnelUrl } = useLocalPreviewUrl(virtualMcpId);
+  /**
+   * A connected `deco serve` (content protocol) stands in the same way: its
+   * app preview is the dev server on this machine. The protocol never runs
+   * site code, so nothing renders in place: the frame is the real app.
+   */
+  const contentBackend = useContentBackend(virtualMcpId, branch);
+  const { connection: serveConnection } = useDecoServeConnection(virtualMcpId);
+  const runsSiteCode = !isProtocolProject(contentBackend);
+  const localPreviewUrl = servePreviewUrl(contentBackend) ?? tunnelUrl;
   const previewUrl = localPreviewUrl ?? lifecycle.previewUrl;
   const devServerReady = !!localPreviewUrl || lifecyclePhase === "running";
 
@@ -485,11 +516,13 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
   const projectDefaultsToCms = session.projectDefault === "cms";
 
   // Base for the `/live/previews` global-section render: production under Fast Preview (no dev server), else the sandbox dev server.
-  const sectionPreviewBase = resolveSectionPreviewBase({
-    sandboxUrl: previewUrl,
-    previewServerUrl,
-    fastPreviewActive: fastPreviewEnabled,
-  });
+  const sectionPreviewBase = runsSiteCode
+    ? resolveSectionPreviewBase({
+        sandboxUrl: previewUrl,
+        previewServerUrl,
+        fastPreviewActive: fastPreviewEnabled,
+      })
+    : null;
 
   // Decofile pages/global sections for the URL bar dropdown. Not gated on the
   // dev server: when it's down we read the committed `.deco/*.gen.json` snapshot
@@ -515,7 +548,7 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
   const decofile = decofileQuery.data;
   const meta = metaQuery.data;
   const pages = decofile
-    ? extractPages(decofile).sort((a, b) => a.name.localeCompare(b.name))
+    ? extractPages(decofile, meta).sort((a, b) => a.name.localeCompare(b.name))
     : [];
   const createPageParams =
     virtualMcpId && branch ? { orgSlug: org.slug, virtualMcpId, branch } : null;
@@ -523,7 +556,9 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
   const globalSections =
     decofile && meta ? extractGlobalSections(decofile, meta) : [];
   const globalLoaders =
-    decofile && meta ? listSavedRunnables(meta, decofile, "loaders") : [];
+    runsSiteCode && decofile && meta
+      ? listSavedRunnables(meta, decofile, "loaders")
+      : [];
   const filteredPages = !pagesSearch
     ? pages
     : (() => {
@@ -593,7 +628,7 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
   // whatever product-search / category loader the running site actually ships.
   // A param with no resolvable source keeps the plain inline input.
   const pathParamSources: Record<string, OptionSource[]> = {};
-  if (devServerReady && previewUrl && meta && decofile) {
+  if (runsSiteCode && devServerReady && previewUrl && meta && decofile) {
     const manifestLoaders = manifestLoaderResolveTypes(meta, "loaders");
     const pageBlock = currentPageKey ? decofile[currentPageKey] : undefined;
     const pageLoaders = collectPageLoaderResolveTypes(
@@ -759,15 +794,17 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
   const inPlaceRenderEnabled =
     agent?.id === virtualMcpId && agent.metadata?.fastPreviewInPlace === true;
   // Local renders fake edits in place against the tunnel's `/live/previews`.
-  const inPlaceRenderActive = localPreviewUrl
-    ? display.mode === "sandbox" &&
-      blocksEditingEnabled &&
-      editingMode === "blocks"
-    : display.mode === "production" &&
-      fastPreviewEnabled &&
-      inPlaceRenderEnabled &&
-      blocksEditingEnabled &&
-      editingMode === "blocks";
+  const inPlaceRenderActive = !runsSiteCode
+    ? false
+    : localPreviewUrl
+      ? display.mode === "sandbox" &&
+        blocksEditingEnabled &&
+        editingMode === "blocks"
+      : display.mode === "production" &&
+        fastPreviewEnabled &&
+        inPlaceRenderEnabled &&
+        blocksEditingEnabled &&
+        editingMode === "blocks";
   // Frozen against autosave version bumps, re-latched on page switch — see resolveInPlaceDraftUrl.
   const pinnedDraftUrlRef = useRef<PinnedDraft | null>(null);
   const { pin: nextPinnedDraft, effective: effectiveDraftPreviewUrl } =
@@ -780,32 +817,51 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
   // oxlint-disable-next-line ban-ref-current-assignment/ban-ref-current-assignment -- persist the frozen/relatched pin for the next render's decision
   pinnedDraftUrlRef.current = nextPinnedDraft;
 
+  // The selected variant: forced variants in the `?__draft=` pointer on a
+  // content-protocol (v8) site, `x-deco-matchers-override` on a legacy one.
+  const variantOverride = workspace.state.variantOverride ?? [];
+  const matcherOverride = runsSiteCode ? variantOverride : [];
+  const forcedVariants = runsSiteCode ? [] : variantOverride;
+  // A connected `deco serve` has no drafts: a pointer to it carries only the
+  // forced variants. With none, `off` drops a pointer the draft cookie kept.
+  const servePointer =
+    serveConnection && servePreviewUrl(contentBackend)
+      ? (buildServeDraftPointer(serveConnection.endpoint, forcedVariants) ??
+        DRAFT_OFF)
+      : null;
+
   const iframeSrc = withDecoFBT(
     display.mode === "sandbox" && externalOriginReady
       ? withVariantMatcherOverride(
           withDeviceHint(
-            directPreviewUrl ??
-              resolvePreviewUrl(resolvedPath, display.iframeBase!) ??
-              display.iframeBase!,
+            withDraftPointer(
+              directPreviewUrl ??
+                resolvePreviewUrl(resolvedPath, display.iframeBase!) ??
+                display.iframeBase!,
+              servePointer,
+            ),
             previewDeviceSize,
           ),
-          workspace.state.variantOverride ?? [],
+          matcherOverride,
         )
       : display.mode === "production" && externalOriginReady
         ? // Fast Preview's draft route honours the variant matcher override like the sandbox dev server, so append it here too.
           withVariantMatcherOverride(
             withDeviceHint(
-              // Waking pill up ⇒ no draft is renderable yet, so ask for published.
-              withDraftPointer(
-                directPreviewUrl ??
-                  effectiveDraftPreviewUrl ??
-                  resolvePreviewUrl(resolvedPath, display.iframeBase!) ??
-                  display.iframeBase!,
-                display.showWakingPill ? DRAFT_OFF : null,
+              withForcedVariantsInDraftUrl(
+                // Waking pill up ⇒ no draft is renderable yet, so ask for published.
+                withDraftPointer(
+                  directPreviewUrl ??
+                    effectiveDraftPreviewUrl ??
+                    resolvePreviewUrl(resolvedPath, display.iframeBase!) ??
+                    display.iframeBase!,
+                  display.showWakingPill ? DRAFT_OFF : null,
+                ),
+                forcedVariants,
               ),
               previewDeviceSize,
             ),
-            workspace.state.variantOverride ?? [],
+            matcherOverride,
           )
         : null,
   );
@@ -856,8 +912,8 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
     display.mode === "production"
       ? productionOpenTabBase
         ? withVariantMatcherOverride(
-            productionOpenTabBase,
-            workspace.state.variantOverride ?? [],
+            withForcedVariantsInDraftUrl(productionOpenTabBase, forcedVariants),
+            matcherOverride,
           )
         : null
       : (iframeSrc ?? display.iframeBase);
@@ -1042,10 +1098,7 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
     });
     if (!req) return;
     // Carry the selected variant like the reload-based `iframeSrc` does; else the runtime renders the default variant.
-    const src = withVariantMatcherOverride(
-      req.src,
-      workspace.state.variantOverride ?? [],
-    );
+    const src = withVariantMatcherOverride(req.src, matcherOverride);
     win.postMessage(
       { type: "cms-editor::render", src, body: req.body },
       origin,
@@ -1315,6 +1368,37 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
   // Only a moved or restarted dev server; file edits reload the page themselves.
   useSandboxReloadHandler(reloadPreviewPreservingScroll);
 
+  // A connected `deco serve` is the exception: a save rewrites the site's
+  // content module, which only the server imports, so the dev server may
+  // swap it without reloading the page in the frame. A new content revision
+  // (a save here, or a read that found the files changed) waits for the
+  // frame to reload itself, as a dev server that reloads on content changes
+  // does, and reloads it otherwise.
+  const contentCacheKey = useDecofileCacheKey(createPageParams);
+  const contentRevision = useContentRevision(
+    servePreviewUrl(contentBackend) ? contentCacheKey : "",
+  );
+  const shownRevisionRef = useRef(contentRevision);
+  // oxlint-disable-next-line ban-use-effect/ban-use-effect -- imperative iframe reload in response to a content revision the query cache moved
+  useEffect(() => {
+    const shown = shownRevisionRef.current;
+    shownRevisionRef.current = contentRevision;
+    if (!shown || !contentRevision || shown === contentRevision) return;
+    const iframe = previewIframeRef.current;
+    if (!iframe) return;
+    const reloadedItself = () => clearTimeout(timer);
+    iframe.addEventListener("load", reloadedItself, { once: true });
+    const timer = setTimeout(() => {
+      iframe.removeEventListener("load", reloadedItself);
+      reloadPreviewPreservingScroll();
+    }, SERVE_SELF_RELOAD_WAIT_MS);
+    return () => {
+      clearTimeout(timer);
+      iframe.removeEventListener("load", reloadedItself);
+    };
+    // oxlint-disable-next-line react-hooks/exhaustive-deps -- reload on a revision change only; the reload reads refs
+  }, [contentRevision]);
+
   const handleDeviceToggle = () => {
     const idx = DEVICE_CYCLE.indexOf(previewDeviceSize);
     setPreviewDeviceSize(DEVICE_CYCLE[(idx + 1) % DEVICE_CYCLE.length]!);
@@ -1456,8 +1540,12 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
     }
   };
 
-  const showPreviewToolbar =
-    previewSurfaceActive && (daemonReady || display.mode === "production");
+  const showPreviewToolbar = showPreviewToolbarFor({
+    previewSurfaceActive,
+    daemonReady,
+    production: display.mode === "production",
+    servePreviewUrl: servePreviewUrl(contentBackend),
+  });
 
   /** The page selector shares the exact project-level gate used by Content and
    *  Blocks. Session runtime and metadata readiness do not change the topbar's
@@ -1722,7 +1810,9 @@ export function PreviewContent({ virtualMcpId }: { virtualMcpId: string }) {
 
   // Desktop composition (portaled into the panel header's centre slot).
 
-  const canVisualEdit = display.mode === "sandbox";
+  // A v7 site keeps visual editing as before; a v8 one needs a chat to ask
+  // (none in the account-less `/site-editor`).
+  const canVisualEdit = (runsSiteCode || hasChat) && display.mode === "sandbox";
 
   // Desktop stays fluid until the canvas is narrower than its logical width; then (and always for mobile/tablet) the frame scales to fit.
   const previewViewport = PREVIEW_VIEWPORTS[previewDeviceSize];
diff --git a/apps/web/src/components/sections-editor/sections-editor.tsx b/apps/web/src/components/sections-editor/sections-editor.tsx
index e462bd31e2..276fe5388b 100644
--- a/apps/web/src/components/sections-editor/sections-editor.tsx
+++ b/apps/web/src/components/sections-editor/sections-editor.tsx
@@ -25,7 +25,7 @@ import {
 import { cn } from "@decocms/ui/lib/utils.ts";
 import { VariantRenameDialog } from "./variant-rename-dialog";
 import { toast } from "sonner";
-import { useDecofile } from "./use-decofile";
+import { useDecofile, useDecofileCacheKey } from "./use-decofile";
 import { useLiveMeta } from "./use-live-meta";
 import { useDeleteBlock } from "./use-delete-block";
 import {
@@ -50,6 +50,8 @@ import { PageVariantTabs, VariantTabIcon } from "./page-variant-tabs";
 import { MakeReusableModal } from "./make-reusable-modal";
 import { AddSectionModal } from "./add-section-modal";
 import { useSectionPreviewBase } from "./use-section-preview-base";
+import { useContentBackend } from "./use-content-backend";
+import { isProtocolProject } from "./content-backend";
 import type { SectionCatalogEntry } from "./section-catalog";
 import { SectionVariantList } from "./section-variant-list";
 import type { Crumb } from "./schema-form-breadcrumb";
@@ -114,6 +116,10 @@ import {
   buildSectionVariantOverrideParams,
   type PageVariantInfo,
 } from "./variant-matcher-override";
+import {
+  buildPageForcedVariants,
+  buildSectionForcedVariants,
+} from "./variant-draft-pointer";
 import { PageJsonDialog } from "./page-json-dialog";
 import { createReferencedBlockSaver } from "./save-referenced-block";
 import { formatMatcher } from "./format-matcher";
@@ -188,9 +194,11 @@ export function SectionsEditor({
   onFocusedBlockChange?: (blockKey: string | null) => void;
   /**
    * Called when the selected section variant changes so the host can force the
-   * preview iframe to render that variant via `x-deco-matchers-override`.
-   * Passes `null` when no variant override should be applied (non-multivariate
-   * section, or nothing selected).
+   * preview iframe to render that variant: `x-deco-matchers-override` params on
+   * a legacy (v7) site, forced variants for the `?__draft=` pointer on a
+   * content-protocol (v8) site (see variant-draft-pointer). Passes `null` when
+   * no variant override should be applied (non-multivariate section, or
+   * nothing selected).
    */
   onVariantPreviewOverride?: (params: string[] | null) => void;
 }) {
@@ -216,8 +224,17 @@ export function SectionsEditor({
   // back to the Fast Preview production deployment while the sandbox boots.
   const sectionPreviewBase = useSectionPreviewBase({
     virtualMcpId,
+    branch,
     sandboxUrl: previewUrl,
   });
+  // The content protocol never runs site code: no rendered gallery (cards show
+  // the schema's name, description and image) and no loader-backed pickers.
+  const contentBackend = useContentBackend(virtualMcpId, branch);
+  const protocolProject = isProtocolProject(contentBackend);
+  // v8 has no async rendering (migration strips Lazy wrappers): hidden once
+  // the site is known to be v8, shown as before otherwise.
+  const asyncRenderAvailable = !protocolProject;
+  const galleryAvailable = !!sectionPreviewBase || protocolProject;
 
   const [selectedSectionIndex, setSelectedSectionIndex] = useState<
     number | null
@@ -319,7 +336,10 @@ export function SectionsEditor({
   );
 
   const queryClient = useQueryClient();
-  const decofileCacheKey = `${orgSlug}/${virtualMcpId}/${branch}`;
+  const decofileCacheKey = useDecofileCacheKey(
+    { orgSlug, virtualMcpId, branch },
+    { tunnel: false },
+  );
   const pageBlockSave = useDebouncedSaveBlock({
     orgSlug,
     virtualMcpId,
@@ -364,12 +384,7 @@ export function SectionsEditor({
       { blockKey: refKey, data },
       {
         onSuccess: () => onSaved?.(),
-        onError: (err) =>
-          toast.error(
-            t("sectionsEditor.sectionsEditor.saveFailed", {
-              error: err.message,
-            }),
-          ),
+        onError: saveBlock.reportError,
       },
     );
   });
@@ -434,7 +449,7 @@ export function SectionsEditor({
     );
   }
 
-  const pages = extractPages(decofile);
+  const pages = extractPages(decofile, meta);
   const isGlobalBlockMode = !!activeGlobalBlockKey;
   const activePage = isGlobalBlockMode
     ? null
@@ -576,12 +591,10 @@ export function SectionsEditor({
       onVariantPreviewOverride(null);
       return;
     }
-    const params = buildPageVariantOverrideParams(
-      activePageKey,
-      { multivariate: true, index, variants },
-      decofile,
-      meta,
-    );
+    const page = { multivariate: true, index, variants };
+    const params = protocolProject
+      ? buildPageForcedVariants(activePageKey, page)
+      : buildPageVariantOverrideParams(activePageKey, page, decofile, meta);
     onVariantPreviewOverride(params.length > 0 ? params : null);
   };
 
@@ -615,26 +628,24 @@ export function SectionsEditor({
       return;
     }
     const pageInfo = currentPageVariantInfo();
-    const pageParams = buildPageVariantOverrideParams(
-      activePageKey,
-      pageInfo,
-      decofile,
-      meta,
-    );
+    const pageParams = protocolProject
+      ? buildPageForcedVariants(activePageKey, pageInfo)
+      : buildPageVariantOverrideParams(activePageKey, pageInfo, decofile, meta);
     if (!mvObj || sectionIndex < 0) {
       onVariantPreviewOverride(pageParams.length > 0 ? pageParams : null);
       return;
     }
-    const sectionParams = buildSectionVariantOverrideParams({
+    const section = {
       pageKey: activePageKey,
       page: pageInfo,
       sectionIndex,
       sectionLazy: parsedSections[sectionIndex]?.isLazy ?? false,
       mvObj,
       selectedVariantIndex: variantIndex,
-      decofile,
-      meta,
-    });
+    };
+    const sectionParams = protocolProject
+      ? buildSectionForcedVariants(section)
+      : buildSectionVariantOverrideParams({ ...section, decofile, meta });
     const params = [...pageParams, ...sectionParams];
     onVariantPreviewOverride(params.length > 0 ? params : null);
   };
@@ -724,7 +735,7 @@ export function SectionsEditor({
     virtualMcpId,
     branch,
     threadId,
-    previewUrl: previewUrl ?? undefined,
+    previewUrl: protocolProject ? undefined : (previewUrl ?? undefined),
     siteSlug: agentSiteSlug,
   };
 
@@ -768,12 +779,7 @@ export function SectionsEditor({
       { blockKey: activePageKey, data: fullPageData },
       {
         onSuccess: () => options?.onSuccess?.() ?? onSaved?.(),
-        onError: (err) =>
-          toast.error(
-            t("sectionsEditor.sectionsEditor.saveFailed", {
-              error: err.message,
-            }),
-          ),
+        onError: saveBlock.reportError,
       },
     );
   };
@@ -832,12 +838,7 @@ export function SectionsEditor({
           { blockKey, data: nextValue },
           {
             onSuccess: () => onSaved?.(),
-            onError: (err) =>
-              toast.error(
-                t("sectionsEditor.sectionsEditor.saveFailed", {
-                  error: err.message,
-                }),
-              ),
+            onError: saveBlock.reportError,
           },
         );
         return;
@@ -920,12 +921,7 @@ export function SectionsEditor({
         { blockKey: latestPageKey, data: fullPageData },
         {
           onSuccess: () => onSaved?.(),
-          onError: (err) =>
-            toast.error(
-              t("sectionsEditor.sectionsEditor.saveFailed", {
-                error: err.message,
-              }),
-            ),
+          onError: saveBlock.reportError,
         },
       );
     };
@@ -1424,7 +1420,7 @@ export function SectionsEditor({
   const handleMakeReusableSubmit = async (blockId: string) => {
     if (makeReusableIndex === null || !activePageKey) return;
 
-    const validationError = validateBlockId(blockId, decofile);
+    const validationError = validateBlockId(blockId, decofile, meta);
     if (validationError) {
       toast.error(validationError);
       return;
@@ -1504,7 +1500,7 @@ export function SectionsEditor({
   const availableMatcherGlobals =
     meta && decofile ? extractMatcherGlobals(meta, decofile) : [];
   const canAddSection =
-    !isGlobalBlockMode && !!(sectionPreviewBase && meta && decofile);
+    !isGlobalBlockMode && !!(galleryAvailable && meta && decofile);
 
   const ruleSchema =
     ruleResolveType && meta ? resolveSchema(ruleResolveType, meta) : null;
@@ -1585,12 +1581,7 @@ export function SectionsEditor({
           },
           {
             onSuccess: () => onSaved?.(),
-            onError: (err) =>
-              toast.error(
-                t("sectionsEditor.sectionsEditor.saveFailed", {
-                  error: err.message,
-                }),
-              ),
+            onError: saveBlock.reportError,
           },
         );
         return;
@@ -1608,12 +1599,7 @@ export function SectionsEditor({
         { blockKey: latestPageKey, data: fullPageData },
         {
           onSuccess: () => onSaved?.(),
-          onError: (err) =>
-            toast.error(
-              t("sectionsEditor.sectionsEditor.saveFailed", {
-                error: err.message,
-              }),
-            ),
+          onError: saveBlock.reportError,
         },
       );
     }, AUTOSAVE_DELAY);
@@ -1763,12 +1749,7 @@ export function SectionsEditor({
           },
           {
             onSuccess: () => onSaved?.(),
-            onError: (err) =>
-              toast.error(
-                t("sectionsEditor.sectionsEditor.saveFailed", {
-                  error: err.message,
-                }),
-              ),
+            onError: saveBlock.reportError,
           },
         );
         return;
@@ -1798,12 +1779,7 @@ export function SectionsEditor({
         { blockKey: latestPageKey, data: fullPageData },
         {
           onSuccess: () => onSaved?.(),
-          onError: (err) =>
-            toast.error(
-              t("sectionsEditor.sectionsEditor.saveFailed", {
-                error: err.message,
-              }),
-            ),
+          onError: saveBlock.reportError,
         },
       );
     }, AUTOSAVE_DELAY);
@@ -2144,12 +2120,7 @@ export function SectionsEditor({
           setRuleFormValue(null);
           setRuleResolveType(null);
         },
-        onError: (err) =>
-          toast.error(
-            t("sectionsEditor.sectionsEditor.saveFailed", {
-              error: err.message,
-            }),
-          ),
+        onError: saveBlock.reportError,
       },
     );
   };
@@ -2214,12 +2185,7 @@ export function SectionsEditor({
             }
           })();
         },
-        onError: (err) =>
-          toast.error(
-            t("sectionsEditor.sectionsEditor.saveFailed", {
-              error: err.message,
-            }),
-          ),
+        onError: saveBlock.reportError,
       },
     );
   };
@@ -2448,7 +2414,7 @@ export function SectionsEditor({
       }
 
       const blockId = suggestBlockId(trimmed);
-      const validationError = validateBlockId(blockId, latestDecofile);
+      const validationError = validateBlockId(blockId, latestDecofile, meta);
       if (validationError) {
         toast.error(validationError);
         return;
@@ -2615,7 +2581,7 @@ export function SectionsEditor({
       }
 
       const blockId = suggestBlockId(trimmed);
-      const validationError = validateBlockId(blockId, latestDecofile);
+      const validationError = validateBlockId(blockId, latestDecofile, meta);
       if (validationError) {
         toast.error(validationError);
         return;
@@ -3233,7 +3199,7 @@ export function SectionsEditor({
         onDuplicate={handleDuplicateSection}
         onMakeReusable={setMakeReusableIndex}
         onToggleHidden={handleToggleHidden}
-        onToggleLazy={handleToggleLazy}
+        onToggleLazy={asyncRenderAvailable ? handleToggleLazy : undefined}
         onAddVariant={handleAddSectionVariant}
         onDetach={handleDetachSection}
         onAddSection={() => setAddSectionOpen(true)}
@@ -3267,6 +3233,7 @@ export function SectionsEditor({
           onInnerChange={handleSeoInnerChange}
           onClearForm={clearSeoForm}
           onBumpFormKey={bumpSeoFormKey}
+          asyncRenderAvailable={asyncRenderAvailable}
         />
       ) : (
         <div className="px-3 py-6 text-center text-xs text-muted-foreground">
@@ -3300,6 +3267,7 @@ export function SectionsEditor({
               onInnerChange={handleSeoInnerChange}
               onClearForm={clearSeoForm}
               onBumpFormKey={bumpSeoFormKey}
+              asyncRenderAvailable={asyncRenderAvailable}
             />
           ) : (
             <div className="px-3 py-6 text-center text-xs text-muted-foreground">
@@ -3660,7 +3628,7 @@ export function SectionsEditor({
           onSubmit={handleMakeReusableSubmit}
         />
 
-        {sectionPreviewBase && (
+        {galleryAvailable && (
           <AddSectionModal
             open={addSectionOpen}
             onOpenChange={(open) => {
diff --git a/apps/web/src/components/sections-editor/use-section-preview-base.ts b/apps/web/src/components/sections-editor/use-section-preview-base.ts
index 53ab98e078..2c7512e499 100644
--- a/apps/web/src/components/sections-editor/use-section-preview-base.ts
+++ b/apps/web/src/components/sections-editor/use-section-preview-base.ts
@@ -1,6 +1,8 @@
 import { useSessionRuntime } from "@/hooks/use-session-runtime";
 import { useLocalPreviewUrl } from "@/hooks/use-local-preview-url";
 import { resolveSectionPreviewBase } from "./section-preview-url";
+import { useContentBackend } from "./use-content-backend";
+import { isProtocolProject } from "./content-backend";
 
 /**
  * Effective base origin for the Add Section gallery previews.
@@ -14,11 +16,15 @@ import { resolveSectionPreviewBase } from "./section-preview-url";
  */
 export function useSectionPreviewBase(input: {
   virtualMcpId: string;
+  branch: string;
   sandboxUrl: string | null | undefined;
 }): string | null {
   const { previewServerUrl, runtime } = useSessionRuntime(input.virtualMcpId);
   const { url: localPreviewUrl } = useLocalPreviewUrl(input.virtualMcpId);
+  const backend = useContentBackend(input.virtualMcpId, input.branch);
   const active = runtime === "cms";
+  // The content protocol never runs site code, so nothing renders a preview.
+  if (isProtocolProject(backend)) return null;
   // Local tunnel is a live deco dev server: render the gallery against it.
   if (localPreviewUrl) return localPreviewUrl;
   return resolveSectionPreviewBase({
diff --git a/apps/web/src/layouts/main-panel-tabs/preview-tab.tsx b/apps/web/src/layouts/main-panel-tabs/preview-tab.tsx
index 2860e1a56c..0674d8bb8b 100644
--- a/apps/web/src/layouts/main-panel-tabs/preview-tab.tsx
+++ b/apps/web/src/layouts/main-panel-tabs/preview-tab.tsx
@@ -1,8 +1,10 @@
 import { useState } from "react";
+import { NewBlocksEditorProvider } from "@/hooks/use-new-blocks-editor";
 import { useChatTask } from "@/components/chat/chat-context";
 import { PreviewContent } from "@/components/sandbox/preview/preview";
 import { agentHasClonableSource } from "@/lib/agent-capabilities";
 import { useVirtualMCP } from "@/sdk";
+import { useDecoServeConnection } from "@/hooks/use-deco-serve-connection";
 import { Button } from "@decocms/ui/components/button.tsx";
 import { EmptyState } from "@/components/empty-state";
 import { GitHubIcon } from "@/components/icons/github-icon";
@@ -14,6 +16,7 @@ import { useTaskMetadata } from "./use-task-metadata";
 export function PreviewTab({ virtualMcpId }: { virtualMcpId: string }) {
   const t = useT();
   const entity = useVirtualMCP(virtualMcpId);
+  const { connection: serveConnection } = useDecoServeConnection(virtualMcpId);
   const { activeTask, taskId, currentBranch } = useChatTask();
   const threadMetadata = useTaskMetadata(taskId);
   const [pickerOpen, setPickerOpen] = useState(false);
@@ -30,7 +33,8 @@ export function PreviewTab({ virtualMcpId }: { virtualMcpId: string }) {
       agentHasClonableSource(activeTask?.metadata),
   });
 
-  if (previewSource === "none") {
+  // A connected `deco serve` is a source of its own (`/site-editor` has no repo).
+  if (previewSource === "none" && !serveConnection) {
     return (
       <>
         <EmptyState
@@ -58,5 +62,9 @@ export function PreviewTab({ virtualMcpId }: { virtualMcpId: string }) {
     );
   }
 
-  return <PreviewContent virtualMcpId={virtualMcpId} />;
+  return (
+    <NewBlocksEditorProvider>
+      <PreviewContent virtualMcpId={virtualMcpId} />
+    </NewBlocksEditorProvider>
+  );
 }
diff --git a/apps/web/src/layouts/main-panel-tabs/use-task-metadata.ts b/apps/web/src/layouts/main-panel-tabs/use-task-metadata.ts
index fa60699fbc..9a0b731659 100644
--- a/apps/web/src/layouts/main-panel-tabs/use-task-metadata.ts
+++ b/apps/web/src/layouts/main-panel-tabs/use-task-metadata.ts
@@ -12,7 +12,8 @@
  * archived-thread fallback, and `localHit` always wins over it.
  *
  * `taskId: null` — a destination route with no thread open — resolves to `null`
- * without touching the wire.
+ * without touching the wire. Outside any thread store (the account-less
+ * `/site-editor`, which has no chat) there are no local rows to read.
  */
 
 import { useSyncExternalStore } from "react";
@@ -20,17 +21,21 @@ import { useSuspenseQuery } from "@tanstack/react-query";
 import { useProjectContext } from "@/sdk";
 import { KEYS } from "@/lib/query-keys";
 import { useStudioTools } from "@/lib/studio-tools";
-import { useThreadManager } from "@/components/chat/store/hooks";
+import { useOptionalThreadManager } from "@/components/chat/store/hooks";
 import type { ThreadMetadata } from "@decocms/shared/entities";
 import type { Task } from "@/components/chat/task/types";
 
+const NO_THREADS: Task[] = [];
+const noSubscription = () => () => {};
+const noThreads = () => NO_THREADS;
+
 export function useTaskMetadata(taskId: string | null): ThreadMetadata | null {
   const { org } = useProjectContext();
   const studio = useStudioTools();
-  const manager = useThreadManager();
+  const manager = useOptionalThreadManager();
   const threads = useSyncExternalStore(
-    manager.threads.subscribe,
-    manager.threads.get,
+    manager?.threads.subscribe ?? noSubscription,
+    manager?.threads.get ?? noThreads,
   );
   const localHit =
     taskId === null ? null : (threads.find((t) => t.id === taskId) ?? null);
diff --git a/knip.jsonc b/knip.jsonc
index cb9820bcdb..b31c10b75a 100644
--- a/knip.jsonc
+++ b/knip.jsonc
@@ -83,10 +83,6 @@
       "exports"
     ],
     "apps/web/src/hooks/use-deco-serve-connection.ts": ["exports"],
-    "apps/web/src/components/sections-editor/content-protocol-api.ts": [
-      "exports"
-    ],
-    "apps/web/src/hooks/use-new-blocks-editor.ts": ["exports"],
     "apps/web/src/components/sections-editor/deco-serve-notices.tsx": [
       "exports"
     ],