diff --git a/cmd/wsh/cmd/wshcmd-root.go b/cmd/wsh/cmd/wshcmd-root.go
index 7e53503d..784a9e20 100644
--- a/cmd/wsh/cmd/wshcmd-root.go
+++ b/cmd/wsh/cmd/wshcmd-root.go
@@ -134,7 +134,7 @@ func validateEasyORef(oref string) error {
 	}
 	_, err := uuid.Parse(oref)
 	if err != nil {
-		return fmt.Errorf("invalid object reference (must be UUID, or a positive nonzero integer): %v", err)
+		return fmt.Errorf("invalid object reference (must be UUID, or a positive integer): %v", err)
 	}
 	return nil
 }
diff --git a/frontend/app/block/blockframe.tsx b/frontend/app/block/blockframe.tsx
index 8954eaae..9e9818bc 100644
--- a/frontend/app/block/blockframe.tsx
+++ b/frontend/app/block/blockframe.tsx
@@ -91,12 +91,13 @@ function getViewIconElem(viewIconUnion: string | HeaderIconButton, blockData: Bl
 }
 
 const OptMagnifyButton = React.memo(
-    ({ magnified, toggleMagnify }: { magnified: boolean; toggleMagnify: () => void }) => {
+    ({ magnified, toggleMagnify, disabled }: { magnified: boolean; toggleMagnify: () => void; disabled: boolean }) => {
         const magnifyDecl: HeaderIconButton = {
             elemtype: "iconbutton",
             icon: <MagnifyIcon enabled={magnified} />,
             title: magnified ? "Minimize" : "Magnify",
             click: toggleMagnify,
+            disabled,
         };
         return <IconButton key="magnify" decl={magnifyDecl} className="block-frame-magnify" />;
     }
@@ -104,13 +105,15 @@ const OptMagnifyButton = React.memo(
 
 function computeEndIcons(
     viewModel: ViewModel,
-    magnified: boolean,
-    toggleMagnify: () => void,
-    onClose: () => void,
+    nodeModel: NodeModel,
     onContextMenu: (e: React.MouseEvent<HTMLDivElement>) => void
 ): JSX.Element[] {
     const endIconsElem: JSX.Element[] = [];
     const endIconButtons = util.useAtomValueSafe(viewModel.endIconButtons);
+    const magnified = jotai.useAtomValue(nodeModel.isMagnified);
+    const numLeafs = jotai.useAtomValue(nodeModel.numLeafs);
+    const magnifyDisabled = numLeafs <= 1;
+
     if (endIconButtons && endIconButtons.length > 0) {
         endIconsElem.push(...endIconButtons.map((button, idx) => <IconButton key={idx} decl={button} />));
     }
@@ -121,12 +124,19 @@ function computeEndIcons(
         click: onContextMenu,
     };
     endIconsElem.push(<IconButton key="settings" decl={settingsDecl} className="block-frame-settings" />);
-    endIconsElem.push(<OptMagnifyButton key="unmagnify" magnified={magnified} toggleMagnify={toggleMagnify} />);
+    endIconsElem.push(
+        <OptMagnifyButton
+            key="unmagnify"
+            magnified={magnified}
+            toggleMagnify={nodeModel.toggleMagnify}
+            disabled={magnifyDisabled}
+        />
+    );
     const closeDecl: HeaderIconButton = {
         elemtype: "iconbutton",
         icon: "xmark-large",
         title: "Close",
-        click: onClose,
+        click: nodeModel.onClose,
     };
     endIconsElem.push(<IconButton key="close" decl={closeDecl} className="block-frame-default-close" />);
     return endIconsElem;
@@ -156,13 +166,7 @@ const BlockFrame_Header = ({
         [magnified]
     );
 
-    const endIconsElem = computeEndIcons(
-        viewModel,
-        magnified,
-        nodeModel.toggleMagnify,
-        nodeModel.onClose,
-        onContextMenu
-    );
+    const endIconsElem = computeEndIcons(viewModel, nodeModel, onContextMenu);
     const viewIconElem = getViewIconElem(viewIconUnion, blockData);
     let preIconButtonElem: JSX.Element = null;
     if (preIconButton) {
diff --git a/frontend/app/block/blockutil.tsx b/frontend/app/block/blockutil.tsx
index d4053dda..5c2981c4 100644
--- a/frontend/app/block/blockutil.tsx
+++ b/frontend/app/block/blockutil.tsx
@@ -139,9 +139,13 @@ export function getBlockHeaderIcon(blockIcon: string, blockData: Block): React.R
 
 export const IconButton = React.memo(({ decl, className }: { decl: HeaderIconButton; className?: string }) => {
     const buttonRef = React.useRef<HTMLDivElement>(null);
-    useLongClick(buttonRef, decl.click, decl.longClick);
+    useLongClick(buttonRef, decl.click, decl.longClick, decl.disabled);
     return (
-        <div ref={buttonRef} className={clsx("iconbutton", className)} title={decl.title}>
+        <div
+            ref={buttonRef}
+            className={clsx("iconbutton", className, decl.className, { disabled: decl.disabled })}
+            title={decl.title}
+        >
             {typeof decl.icon === "string" ? <i className={util.makeIconClass(decl.icon, true)} /> : decl.icon}
         </div>
     );
diff --git a/frontend/app/hook/useLongClick.tsx b/frontend/app/hook/useLongClick.tsx
index 21de895b..5b71563f 100644
--- a/frontend/app/hook/useLongClick.tsx
+++ b/frontend/app/hook/useLongClick.tsx
@@ -3,7 +3,7 @@
 
 import { useCallback, useEffect, useRef, useState } from "react";
 
-export const useLongClick = (ref, onClick, onLongClick, ms = 300) => {
+export const useLongClick = (ref, onClick, onLongClick, disabled = false, ms = 300) => {
     const timerRef = useRef(null);
     const [longClickTriggered, setLongClickTriggered] = useState(false);
 
@@ -40,7 +40,7 @@ export const useLongClick = (ref, onClick, onLongClick, ms = 300) => {
     useEffect(() => {
         const element = ref.current;
 
-        if (!element) return;
+        if (!element || disabled) return;
 
         element.addEventListener("mousedown", startPress);
         element.addEventListener("mouseup", stopPress);
diff --git a/frontend/app/view/webview/webview.tsx b/frontend/app/view/webview/webview.tsx
index f07e1307..3bc0212a 100644
--- a/frontend/app/view/webview/webview.tsx
+++ b/frontend/app/view/webview/webview.tsx
@@ -63,15 +63,15 @@ export class WebViewModel implements ViewModel {
             return [
                 {
                     elemtype: "iconbutton",
-                    className: this.shouldDisabledBackButton() ? "disabled" : "",
                     icon: "chevron-left",
                     click: this.handleBack.bind(this),
+                    disabled: this.shouldDisabledBackButton(),
                 },
                 {
                     elemtype: "iconbutton",
-                    className: this.shouldDisabledForwardButton() ? "disabled" : "",
                     icon: "chevron-right",
                     click: this.handleForward.bind(this),
+                    disabled: this.shouldDisabledForwardButton(),
                 },
                 {
                     elemtype: "div",
diff --git a/frontend/layout/lib/layoutModel.ts b/frontend/layout/lib/layoutModel.ts
index 1da6e39f..85663097 100644
--- a/frontend/layout/lib/layoutModel.ts
+++ b/frontend/layout/lib/layoutModel.ts
@@ -439,7 +439,6 @@ export class LayoutModel {
                 }
             } else {
                 this.updateTree();
-                this.setTreeStateAtom();
             }
         }
     }
@@ -448,7 +447,7 @@ export class LayoutModel {
      * Set the upstream tree state atom to the value of the local tree state.
      * @param bumpGeneration Whether to bump the generation of the tree state before setting the atom.
      */
-    setTreeStateAtom(bumpGeneration = true) {
+    setTreeStateAtom(bumpGeneration = false) {
         if (bumpGeneration) {
             this.treeState.generation++;
         }
@@ -460,7 +459,7 @@ export class LayoutModel {
      * This is a hack to ensure that when the updateTree first successfully runs, we set the upstream atom state to persist the initial leaf order.
      * @see updateTree should be the only caller of this method.
      */
-    setTreeStateAtomOnce = lazy(() => this.setTreeStateAtom());
+    setTreeStateAtomOnce = lazy(() => this.setTreeStateAtom(true));
 
     /**
      * Recursively walks the tree to find leaf nodes, update the resize handles, and compute additional properties for each node.
@@ -761,6 +760,7 @@ export class LayoutModel {
                     const isFocused = treeState.focusedNodeId === nodeid;
                     return isFocused;
                 }),
+                numLeafs: this.numLeafs,
                 isMagnified: atom((get) => {
                     const treeState = get(this.treeStateAtom);
                     return treeState.magnifiedNodeId === nodeid;
diff --git a/frontend/layout/lib/types.ts b/frontend/layout/lib/types.ts
index 5c1f45a3..7144a8d8 100644
--- a/frontend/layout/lib/types.ts
+++ b/frontend/layout/lib/types.ts
@@ -328,6 +328,7 @@ export interface NodeModel {
     animationTimeS: number;
     innerRect: Atom<CSSProperties>;
     blockNum: Atom<number>;
+    numLeafs: Atom<number>;
     nodeId: string;
     blockId: string;
     isFocused: Atom<boolean>;
diff --git a/frontend/types/custom.d.ts b/frontend/types/custom.d.ts
index 9e201f67..7c5a5bdd 100644
--- a/frontend/types/custom.d.ts
+++ b/frontend/types/custom.d.ts
@@ -154,6 +154,7 @@ declare global {
         title?: string;
         click?: (e: React.MouseEvent<any>) => void;
         longClick?: (e: React.MouseEvent<any>) => void;
+        disabled?: boolean;
     };
 
     type HeaderTextButton = {