diff --git a/web/src/components/AppSidebar/AppSidebar.tsx b/web/src/components/AppSidebar/AppSidebar.tsx
index 261b980e..c9439ea5 100644
--- a/web/src/components/AppSidebar/AppSidebar.tsx
+++ b/web/src/components/AppSidebar/AppSidebar.tsx
@@ -437,7 +437,7 @@ const GlobalNavigation = () => {
 
   return (
     <TooltipProvider>
-      <nav className={cn("flex h-9 items-center gap-1", SIDEBAR_RAIL_CLASSES)} aria-label="Primary">
+      <nav className={cn("flex h-8 items-center gap-1", SIDEBAR_RAIL_CLASSES)} aria-label="Primary">
         {currentUser && (
           <DropdownMenu
             onOpenChange={(open, eventDetails) => {
@@ -505,7 +505,7 @@ const GlobalNavigation = () => {
                   <span
                     data-sidebar-trailing
                     className={cn(
-                      "absolute -end-0.5 -top-0.5 flex min-w-4 items-center justify-center rounded-full bg-primary px-1 text-[9px] font-semibold leading-4 text-primary-foreground transition-[opacity,scale] duration-200 ease-out motion-reduce:transition-none",
+                      "absolute -end-0.5 top-0 flex min-w-4 items-center justify-center rounded-full bg-primary px-1 text-[9px] font-semibold leading-4 text-primary-foreground transition-[opacity,scale] duration-200 ease-out motion-reduce:transition-none",
                       item.count > 0 ? "scale-100 opacity-100" : "scale-50 opacity-0",
                     )}
                   >
diff --git a/web/src/components/AppSidebar/SpaceSwitcher.tsx b/web/src/components/AppSidebar/SpaceSwitcher.tsx
index 376fa3dc..2d02e9e0 100644
--- a/web/src/components/AppSidebar/SpaceSwitcher.tsx
+++ b/web/src/components/AppSidebar/SpaceSwitcher.tsx
@@ -1,4 +1,4 @@
-import { CheckIcon, ChevronDownIcon, LoaderCircleIcon, type LucideIcon, PlusIcon } from "lucide-react";
+import { CheckIcon, ChevronsUpDownIcon, LoaderCircleIcon, type LucideIcon, PlusIcon } from "lucide-react";
 import { type ReactNode, useRef, useState } from "react";
 import CreateSpaceDialog from "@/components/CreateSpaceDialog";
 import MemosLogo from "@/components/MemosLogo";
@@ -92,7 +92,7 @@ function SpaceSwitcher({ className, size = "md" }: { className?: string; size?:
               aria-label={`${t("space.switch")}: ${currentContextLabel}`}
               title={currentContextLabel}
               className={cn(
-                "group text-start transition-colors hover:bg-sidebar-accent/65 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-inset focus-visible:ring-ring/40",
+                "text-start transition-colors hover:bg-sidebar-accent/65 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-inset focus-visible:ring-ring/40",
                 size === "header" ? sidebarSurfaceVariants({ role: "headerBrand" }) : sidebarSurfaceVariants({ role: "mobileBrand" }),
                 className,
               )}
@@ -127,10 +127,7 @@ function SpaceSwitcher({ className, size = "md" }: { className?: string; size?:
               <MemosLogo compact size={brandSize} />
             )}
           </span>
-          <ChevronDownIcon
-            className="size-3.5 shrink-0 text-muted-foreground/70 transition-transform duration-150 group-data-[popup-open]:rotate-180 motion-reduce:transition-none"
-            strokeWidth={1.8}
-          />
+          <ChevronsUpDownIcon aria-hidden="true" className="size-3.5 shrink-0 text-muted-foreground/70" strokeWidth={1.8} />
         </DropdownMenuTrigger>
         <DropdownMenuContent
           size="sm"
diff --git a/web/src/components/MemoActionMenu/MemoActionMenu.tsx b/web/src/components/MemoActionMenu/MemoActionMenu.tsx
index 10a87c15..b6fb39ee 100644
--- a/web/src/components/MemoActionMenu/MemoActionMenu.tsx
+++ b/web/src/components/MemoActionMenu/MemoActionMenu.tsx
@@ -25,6 +25,7 @@ import {
   DropdownMenuSubTrigger,
   DropdownMenuTrigger,
 } from "@/components/ui/dropdown-menu";
+import { cn } from "@/lib/utils";
 import { State } from "@/types/proto/api/v1/common_pb";
 import { useTranslate } from "@/utils/i18n";
 import { useMemoActionHandlers } from "./hooks";
@@ -63,8 +64,20 @@ const MemoActionMenu = (props: MemoActionMenuProps) => {
 
   return (
     <DropdownMenu>
-      <DropdownMenuTrigger render={<Button variant="ghost" size="icon" className="size-4" />}>
-        <MoreVerticalIcon className="text-muted-foreground" />
+      <DropdownMenuTrigger
+        render={
+          <Button
+            variant="ghost"
+            size="icon-sm"
+            aria-label={t("common.more")}
+            className={cn(
+              "text-muted-foreground/70 hover:text-foreground focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-inset focus-visible:ring-ring/50 data-popup-open:bg-accent data-popup-open:text-accent-foreground",
+              props.className,
+            )}
+          />
+        }
+      >
+        <MoreVerticalIcon className="size-4" strokeWidth={1.8} />
       </DropdownMenuTrigger>
       <DropdownMenuContent align="end" sideOffset={2}>
         {/* Edit actions (non-readonly, non-archived) */}
diff --git a/web/src/components/MemoReactionListView/ReactionSelector.tsx b/web/src/components/MemoReactionListView/ReactionSelector.tsx
index 646a8182..f760bcf8 100644
--- a/web/src/components/MemoReactionListView/ReactionSelector.tsx
+++ b/web/src/components/MemoReactionListView/ReactionSelector.tsx
@@ -4,6 +4,7 @@ import { Popover, PopoverContent, PopoverTrigger } from "@/components/ui/popover
 import { useInstance } from "@/contexts/InstanceContext";
 import { cn } from "@/lib/utils";
 import type { Memo } from "@/types/proto/api/v1/memo_service_pb";
+import { useTranslate } from "@/utils/i18n";
 import { useReactionActions } from "./hooks";
 
 interface Props {
@@ -14,6 +15,7 @@ interface Props {
 
 const ReactionSelector = (props: Props) => {
   const { memo, className, onOpenChange } = props;
+  const t = useTranslate();
   const [open, setOpen] = useState(false);
   const { memoRelatedSetting } = useInstance();
 
@@ -30,17 +32,18 @@ const ReactionSelector = (props: Props) => {
   return (
     <Popover open={open} onOpenChange={handleOpenChange}>
       <PopoverTrigger
-        nativeButton={false}
         render={
-          <span
+          <button
+            type="button"
+            aria-label={t("setting.memo.add-reaction")}
             className={cn(
-              "h-7 w-7 flex justify-center items-center rounded-full border cursor-pointer transition-all hover:opacity-80",
+              "flex size-7 cursor-pointer items-center justify-center rounded-full border text-muted-foreground transition-all hover:opacity-80 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/50",
               className,
             )}
           />
         }
       >
-        <SmilePlusIcon className="w-4 h-4 mx-auto text-muted-foreground" />
+        <SmilePlusIcon className="mx-auto size-4" />
       </PopoverTrigger>
       <PopoverContent align="center" className="max-w-[90vw] sm:max-w-md">
         <div className="grid grid-cols-4 sm:grid-cols-6 md:grid-cols-8 gap-1 max-h-64 overflow-y-auto">
diff --git a/web/src/components/MemoView/components/MemoHeader.tsx b/web/src/components/MemoView/components/MemoHeader.tsx
index 6e37845b..7af50004 100644
--- a/web/src/components/MemoView/components/MemoHeader.tsx
+++ b/web/src/components/MemoView/components/MemoHeader.tsx
@@ -2,6 +2,7 @@ import { BookmarkIcon } from "lucide-react";
 import { useCallback, useState } from "react";
 import { Link } from "react-router-dom";
 import RelativeTime from "@/components/RelativeTime";
+import { Button } from "@/components/ui/button";
 import { Tooltip, TooltipContent, TooltipProvider, TooltipTrigger } from "@/components/ui/tooltip";
 import { useNewMemo } from "@/contexts/NewMemoContext";
 import useNavigateTo from "@/hooks/useNavigateTo";
@@ -21,6 +22,9 @@ import { createMemoNavigationState } from "../navigation";
 import type { MemoHeaderProps } from "../types";
 import MemoSpaceBadge from "./MemoSpaceBadge";
 
+const MEMO_HEADER_ACTION_CLASSES =
+  "size-6 shrink-0 rounded-md border-none bg-transparent text-muted-foreground transition-colors hover:bg-accent hover:text-foreground hover:opacity-100 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-inset focus-visible:ring-ring/50 data-popup-open:bg-accent data-popup-open:text-foreground";
+
 const MemoHeader: React.FC<MemoHeaderProps> = ({ showCreator, showVisibility, showPinned, showSpace }) => {
   const t = useTranslate();
   const [reactionSelectorOpen, setReactionSelectorOpen] = useState(false);
@@ -82,10 +86,14 @@ const MemoHeader: React.FC<MemoHeaderProps> = ({ showCreator, showVisibility, sh
         )}
       </div>
 
-      <div className="flex flex-row justify-end items-center select-none shrink-0 gap-2">
+      <div data-slot="memo-header-actions" className="flex shrink-0 select-none flex-row items-center justify-end gap-1">
         {currentUser && !isArchived && (
           <ReactionSelector
-            className={cn("border-none w-auto h-auto", reactionSelectorOpen && "block!", "block sm:hidden sm:group-hover:block")}
+            className={cn(
+              MEMO_HEADER_ACTION_CLASSES,
+              reactionSelectorOpen && "sm:flex!",
+              "flex sm:hidden sm:group-hover:flex sm:group-focus-within:flex",
+            )}
             memo={memo}
             onOpenChange={setReactionSelectorOpen}
           />
@@ -93,10 +101,8 @@ const MemoHeader: React.FC<MemoHeaderProps> = ({ showCreator, showVisibility, sh
 
         {showVisibility && memo.visibility !== Visibility.PRIVATE && (
           <Tooltip>
-            <TooltipTrigger>
-              <span className="flex justify-center items-center rounded-md hover:opacity-80">
-                <VisibilityIcon visibility={memo.visibility} />
-              </span>
+            <TooltipTrigger aria-label={visibilityOption && t(visibilityOption.labelKey)} className={MEMO_HEADER_ACTION_CLASSES}>
+              <VisibilityIcon visibility={memo.visibility} className="text-current" />
             </TooltipTrigger>
             <TooltipContent>{visibilityOption && t(visibilityOption.labelKey)}</TooltipContent>
           </Tooltip>
@@ -105,8 +111,18 @@ const MemoHeader: React.FC<MemoHeaderProps> = ({ showCreator, showVisibility, sh
         {showPinned && memo.pinned && (
           <TooltipProvider>
             <Tooltip>
-              <TooltipTrigger render={<span className="cursor-pointer" />}>
-                <BookmarkIcon className="w-4 h-auto text-primary" onClick={unpinMemo} />
+              <TooltipTrigger
+                render={
+                  <Button
+                    variant="ghost"
+                    size="icon-sm"
+                    aria-label={t("common.unpin")}
+                    className={cn(MEMO_HEADER_ACTION_CLASSES, "text-primary hover:text-primary data-popup-open:text-primary")}
+                    onClick={unpinMemo}
+                  />
+                }
+              >
+                <BookmarkIcon className="size-4" strokeWidth={1.8} />
               </TooltipTrigger>
               <TooltipContent>
                 <p>{t("common.unpin")}</p>
@@ -115,7 +131,13 @@ const MemoHeader: React.FC<MemoHeaderProps> = ({ showCreator, showVisibility, sh
           </TooltipProvider>
         )}
 
-        <MemoActionMenu memo={memo} parentScope={parentScope} readonly={readonly} onEdit={openEditor} />
+        <MemoActionMenu
+          memo={memo}
+          parentScope={parentScope}
+          readonly={readonly}
+          className={MEMO_HEADER_ACTION_CLASSES}
+          onEdit={openEditor}
+        />
       </div>
     </div>
   );
diff --git a/web/tests/app-sidebar-logo.test.tsx b/web/tests/app-sidebar-logo.test.tsx
index 87641064..81a5bc02 100644
--- a/web/tests/app-sidebar-logo.test.tsx
+++ b/web/tests/app-sidebar-logo.test.tsx
@@ -222,7 +222,8 @@ describe("App sidebar logo", () => {
     expect(switcher).not.toHaveClass("px-1");
     expect(switcher.firstElementChild).not.toHaveClass("flex-1");
     expect(within(switcher).getByText("Memos logo")).toHaveAttribute("data-logo-size", "header");
-    expect(switcher.querySelector(".lucide-chevron-down")).not.toBeNull();
+    expect(switcher.querySelector(".lucide-chevrons-up-down")).not.toBeNull();
+    expect(switcher.querySelector(".lucide-chevron-down")).toBeNull();
     expect(compose).toHaveClass("size-7", "rounded-md", "border", "bg-background", "shadow-xs");
     expect(compose).not.toHaveClass("rounded-full");
 
@@ -398,7 +399,7 @@ describe("App sidebar logo", () => {
     expect(screen.getByRole("link", { name: "Memos logo" })).toHaveAttribute("href", "/explore");
     expect(screen.queryByRole("button", { name: /^space\.switch:/ })).not.toBeInTheDocument();
     const primaryNavigation = screen.getByRole("navigation", { name: "Primary" });
-    expect(primaryNavigation).toHaveClass("h-9", "items-center", "gap-1", "px-3");
+    expect(primaryNavigation).toHaveClass("h-8", "items-center", "gap-1", "px-3");
     expect(primaryNavigation).not.toHaveClass("flex-col");
     const navigation = within(primaryNavigation);
     expectActiveNavPill(navigation.getByRole("link", { name: "common.explore" }), "common.explore");
@@ -523,6 +524,7 @@ describe("App sidebar logo", () => {
     const scopeTrigger = screen.getByRole("button", { name: "common.home" });
     expectActiveNavPill(scopeTrigger, "common.home");
     expect(scopeTrigger.querySelector(".lucide-chevron-down")).toBeInTheDocument();
+    expect(scopeTrigger.querySelector(".lucide-chevrons-up-down")).not.toBeInTheDocument();
     expectCollapsedNavPill(screen.getByRole("link", { name: "common.attachments" }), "common.attachments");
     fireEvent.click(scopeTrigger);
     expect(await screen.findByRole("menuitem", { name: "common.home" })).toBeInTheDocument();
diff --git a/web/tests/memo-action-menu.test.tsx b/web/tests/memo-action-menu.test.tsx
new file mode 100644
index 00000000..a6ffe86d
--- /dev/null
+++ b/web/tests/memo-action-menu.test.tsx
@@ -0,0 +1,49 @@
+import { create } from "@bufbuild/protobuf";
+import { fireEvent, render, screen, waitFor } from "@testing-library/react";
+import { describe, expect, it, vi } from "vitest";
+import MemoActionMenu from "@/components/MemoActionMenu";
+import { State } from "@/types/proto/api/v1/common_pb";
+import { MemoSchema } from "@/types/proto/api/v1/memo_service_pb";
+
+const handlers = vi.hoisted(() => ({
+  handleTogglePinMemoBtnClick: vi.fn(),
+  handleEditMemoClick: vi.fn(),
+  handleToggleMemoStatusClick: vi.fn(),
+  handleCopyLink: vi.fn(),
+  handleCopyContent: vi.fn(),
+  handleCheckAllTaskListItemsClick: vi.fn(),
+  handleUncheckAllTaskListItemsClick: vi.fn(),
+  handleDeleteMemoClick: vi.fn(),
+  confirmDeleteMemo: vi.fn(),
+}));
+
+vi.mock("@/components/ConfirmDialog", () => ({
+  default: () => null,
+}));
+
+vi.mock("@/components/MemoActionMenu/hooks", () => ({
+  useMemoActionHandlers: () => handlers,
+}));
+
+vi.mock("@/utils/i18n", () => ({
+  useTranslate: () => (key: string) => key,
+}));
+
+describe("MemoActionMenu", () => {
+  it("uses the standard compact action surface and preserves its open state", async () => {
+    const memo = create(MemoSchema, { name: "memos/1", state: State.NORMAL, pinned: false });
+    render(<MemoActionMenu memo={memo} parentScope="preserve" />);
+
+    const trigger = screen.getByRole("button", { name: "common.more" });
+    expect(trigger).toHaveClass("size-6", "rounded-md", "hover:bg-accent", "focus-visible:ring-2", "data-popup-open:bg-accent");
+    expect(trigger).toHaveAttribute("aria-haspopup", "menu");
+    expect(trigger).toHaveAttribute("aria-expanded", "false");
+    expect(trigger.querySelector(".lucide-ellipsis-vertical")).toHaveClass("size-4");
+
+    fireEvent.click(trigger);
+
+    await waitFor(() => expect(trigger).toHaveAttribute("aria-expanded", "true"));
+    expect(trigger).toHaveAttribute("data-popup-open");
+    expect(await screen.findByRole("menuitem", { name: "common.pin" })).toBeInTheDocument();
+  });
+});
diff --git a/web/tests/memo-header-navigation.test.tsx b/web/tests/memo-header-navigation.test.tsx
index f7c496dc..1eeda419 100644
--- a/web/tests/memo-header-navigation.test.tsx
+++ b/web/tests/memo-header-navigation.test.tsx
@@ -5,6 +5,7 @@ import MemoHeader from "@/components/MemoView/components/MemoHeader";
 
 const state = vi.hoisted(() => ({
   creator: undefined as { username: string; displayName: string; avatarUrl: string } | undefined,
+  currentUser: undefined as { name: string } | undefined,
 }));
 
 vi.mock("@/components/RelativeTime", () => ({
@@ -12,11 +13,19 @@ vi.mock("@/components/RelativeTime", () => ({
 }));
 
 vi.mock("@/components/MemoActionMenu", () => ({
-  default: () => null,
+  default: ({ className }: { className?: string }) => (
+    <button type="button" aria-label="memo-actions" className={className}>
+      Memo actions
+    </button>
+  ),
 }));
 
 vi.mock("@/components/MemoReactionListView", () => ({
-  ReactionSelector: () => null,
+  ReactionSelector: ({ className }: { className?: string }) => (
+    <button type="button" aria-label="add-reaction" className={className}>
+      Add reaction
+    </button>
+  ),
 }));
 
 vi.mock("@/components/UserAvatar", () => ({
@@ -50,7 +59,7 @@ vi.mock("@/components/MemoView/MemoViewContext", () => ({
   useMemoViewContext: () => ({
     memo: { name: "memos/123", visibility: 1, pinned: false, space: "spaces/product" },
     creator: state.creator,
-    currentUser: undefined,
+    currentUser: state.currentUser,
     parentPage: "/explore?filter=tagSearch%3Awork",
     parentScope: "preserve",
     isArchived: false,
@@ -82,6 +91,34 @@ const LocationProbe = () => {
 describe("MemoHeader navigation", () => {
   beforeEach(() => {
     state.creator = undefined;
+    state.currentUser = undefined;
+  });
+
+  it("uses one compact interaction surface for memo header actions", () => {
+    state.currentUser = { name: "users/alice" };
+
+    render(
+      <MemoryRouter>
+        <MemoHeader />
+      </MemoryRouter>,
+    );
+
+    const reaction = screen.getByRole("button", { name: "add-reaction" });
+    const actions = screen.getByRole("button", { name: "memo-actions" });
+    const actionRail = actions.closest('[data-slot="memo-header-actions"]');
+
+    expect(actionRail).toHaveClass("items-center", "gap-1");
+    expect(reaction).toHaveClass("sm:group-focus-within:flex");
+    for (const action of [reaction, actions]) {
+      expect(action).toHaveClass(
+        "size-6",
+        "rounded-md",
+        "hover:bg-accent",
+        "hover:text-foreground",
+        "focus-visible:ring-2",
+        "data-popup-open:bg-accent",
+      );
+    }
   });
 
   it.each([false, true])("uses a keyboard-operable timestamp and preserves origin when showCreator=%s", (showCreator) => {
diff --git a/web/tests/reaction-selector.test.tsx b/web/tests/reaction-selector.test.tsx
new file mode 100644
index 00000000..c4fc1f26
--- /dev/null
+++ b/web/tests/reaction-selector.test.tsx
@@ -0,0 +1,36 @@
+import { create } from "@bufbuild/protobuf";
+import { fireEvent, render, screen, waitFor } from "@testing-library/react";
+import { describe, expect, it, vi } from "vitest";
+import ReactionSelector from "@/components/MemoReactionListView/ReactionSelector";
+import { MemoSchema } from "@/types/proto/api/v1/memo_service_pb";
+
+vi.mock("@/components/MemoReactionListView/hooks", () => ({
+  useReactionActions: () => ({
+    hasReacted: () => false,
+    handleReactionClick: vi.fn(),
+  }),
+}));
+
+vi.mock("@/contexts/InstanceContext", () => ({
+  useInstance: () => ({ memoRelatedSetting: { reactions: ["👍"] } }),
+}));
+
+vi.mock("@/utils/i18n", () => ({
+  useTranslate: () => (key: string) => key,
+}));
+
+describe("ReactionSelector", () => {
+  it("uses a named native trigger with a visible focus state", async () => {
+    const memo = create(MemoSchema, { name: "memos/1", reactions: [] });
+    render(<ReactionSelector memo={memo} />);
+
+    const trigger = screen.getByRole("button", { name: "setting.memo.add-reaction" });
+    expect(trigger).toHaveClass("size-7", "rounded-full", "focus-visible:ring-2");
+    expect(trigger).toHaveAttribute("aria-expanded", "false");
+
+    fireEvent.click(trigger);
+
+    await waitFor(() => expect(trigger).toHaveAttribute("aria-expanded", "true"));
+    expect(screen.getByRole("button", { name: "👍" })).toBeInTheDocument();
+  });
+});
diff --git a/web/tests/space-switcher.test.tsx b/web/tests/space-switcher.test.tsx
index 3143728a..3c5012b5 100644
--- a/web/tests/space-switcher.test.tsx
+++ b/web/tests/space-switcher.test.tsx
@@ -64,7 +64,11 @@ describe("SpaceSwitcher", () => {
   it("lists Memos, every available Space, and the create entry", async () => {
     render(<SpaceSwitcher />);
 
-    fireEvent.click(screen.getByRole("button", { name: "space.switch: common.memos" }));
+    const trigger = screen.getByRole("button", { name: "space.switch: common.memos" });
+    expect(trigger).toHaveAttribute("aria-haspopup", "menu");
+    expect(trigger).toHaveAttribute("aria-expanded", "false");
+    fireEvent.click(trigger);
+    expect(trigger).toHaveAttribute("aria-expanded", "true");
 
     expect(await screen.findByRole("menuitemradio", { name: "Memos" })).toHaveAttribute("aria-checked", "true");
     const productRow = screen.getByRole("menuitemradio", { name: "Product" });
@@ -157,8 +161,8 @@ describe("SpaceSwitcher", () => {
     expect(trigger).not.toHaveClass("px-1");
     expect(title).toHaveClass("text-[14px]", "font-semibold", "leading-5");
     expect(mark).toHaveClass("size-5", "rounded-[5px]");
-    expect(trigger.querySelector(".lucide-chevron-down")).not.toBeNull();
-    expect(trigger.querySelector(".lucide-chevrons-up-down")).toBeNull();
+    expect(trigger.querySelector(".lucide-chevrons-up-down")).not.toBeNull();
+    expect(trigger.querySelector(".lucide-chevron-down")).toBeNull();
   });
 
   it("keeps duplicate identity in the header label but out of its geometry", () => {