diff --git a/docs/tui.md b/docs/tui.md
index d1ada41b..52d35561 100644
--- a/docs/tui.md
+++ b/docs/tui.md
@@ -53,7 +53,7 @@ uppercase belongs to Labels:
 | `t` | trash |
 | `!` | mark as spam |
 | `-` / `+` | ignore / stop ignoring |
-| Space | select the thread for a bulk action |
+| Space or `x` | select the thread for a bulk action |
 | Ctrl+B | preview every bulk-reply recipient, then write one reply to every selected thread |
 | Ctrl+U | recall a delayed bulk reply while HEY's undo window is open |
 | Ctrl+S | open The Screener |
@@ -109,7 +109,7 @@ scroll, the same way the mail list does.
 The Imbox can wear cover art, the way the HEY web app does: everything you have already
 read goes under it, so the box ends at what still wants your attention instead of trailing
 off into a month of receipts. The divider stays and says how much is under there — press
-`x` to peek, `x` again to close it, or `9` to open Previously Seen on its own screen.
+`z` to peek, `z` again to close it, or `9` to open Previously Seen on its own screen.
 
 Press Ctrl+V to choose one: `blobs`, `grid`, `peace`, `terrazzo`, `topo` or `waves`, the
 same six covers redrawn as characters, so they work in any terminal rather than only the
diff --git a/internal/tui/bulk_reply.go b/internal/tui/bulk_reply.go
index 8af2c226..a31afe79 100644
--- a/internal/tui/bulk_reply.go
+++ b/internal/tui/bulk_reply.go
@@ -287,7 +287,7 @@ func replyNoun(count int) string {
 func (v *mailView) startBulkReply() tea.Cmd {
 	postingIDs := v.actionList().selectedIDs()
 	if len(postingIDs) == 0 {
-		v.notice = "Select threads with space before starting a bulk reply"
+		v.notice = "Select threads with space or x before starting a bulk reply"
 		return nil
 	}
 	requestID, ctx := v.requests.begin(v.vc.ctx, mailRequestBulkReply)
diff --git a/internal/tui/bulk_reply_test.go b/internal/tui/bulk_reply_test.go
index 5c39e62c..c70f62f1 100644
--- a/internal/tui/bulk_reply_test.go
+++ b/internal/tui/bulk_reply_test.go
@@ -120,7 +120,7 @@ func TestTUIBulkReplyRequiresExplicitSelection(t *testing.T) {
 	if cmd := view.HandleContentKey(keyPress("ctrl+b")); cmd != nil {
 		t.Fatal("bulk reply without a selection should not make a request")
 	}
-	if view.notice != "Select threads with space before starting a bulk reply" {
+	if view.notice != "Select threads with space or x before starting a bulk reply" {
 		t.Errorf("notice = %q", view.notice)
 	}
 	if requests := state.snapshot(); len(requests) != 0 {
diff --git a/internal/tui/calendar_views.go b/internal/tui/calendar_views.go
index 26bffe68..62ec5ae8 100644
--- a/internal/tui/calendar_views.go
+++ b/internal/tui/calendar_views.go
@@ -652,7 +652,7 @@ func renderDayView(events, habits, countdowns []Recording, anchor, now time.Time
 
 	// The day names itself above its hours — the subnav carries the calendar and the
 	// view mode, so which day this is has nowhere else to be said — and the keys that
-	// move it sit on the same line, where the cover puts "x to peek".
+	// move it sit on the same line, where the cover puts "z to peek".
 	b.WriteString(hintedSectionHeader(anchor.Local().Format("Monday, January 2"), hint, width))
 	b.WriteString("\n")
 
diff --git a/internal/tui/content.go b/internal/tui/content.go
index 84d2c38d..4a592de8 100644
--- a/internal/tui/content.go
+++ b/internal/tui/content.go
@@ -569,7 +569,7 @@ func (c *contentList) view() string {
 
 		if label := c.sectionLabelAt(i); label != "" {
 			if c.cover != coverNone && sectionOf(p) == sectionPreviouslySeen {
-				fmt.Fprintln(&b, hintedSectionHeader(label, "x to cover", c.width))
+				fmt.Fprintln(&b, hintedSectionHeader(label, "z to cover", c.width))
 			} else {
 				fmt.Fprintln(&b, sectionHeader(label, c.width))
 			}
@@ -695,7 +695,7 @@ func (c *contentList) view() string {
 // The threads themselves are not rendered at all — that is the whole point of a
 // cover, and it is why the art can have every row the postings did not use.
 func (c *contentList) coverView(hidden, rowsUsed int) string {
-	hint := fmt.Sprintf("%d hidden · x to peek", hidden)
+	hint := fmt.Sprintf("%d hidden · z to peek", hidden)
 	header := hintedSectionHeader(sectionPreviouslySeen.label(), hint, c.width)
 
 	rows := c.height - rowsUsed - 1
@@ -716,7 +716,7 @@ func sectionHeader(label string, width int) string {
 }
 
 // hintedSectionHeader is a section label with a hint on its right, where the HEY web
-// app puts a section's buttons: "Previously Seen ──── 34 hidden · x to peek", or
+// app puts a section's buttons: "Previously Seen ──── 34 hidden · z to peek", or
 // "Habits ──── b to manage".
 func hintedSectionHeader(label, hint string, width int) string {
 	rule := lipgloss.NewStyle().Foreground(colorChrome)
diff --git a/internal/tui/cover_picker.go b/internal/tui/cover_picker.go
index fe30369d..9e8a5745 100644
--- a/internal/tui/cover_picker.go
+++ b/internal/tui/cover_picker.go
@@ -95,7 +95,7 @@ func (p *coverPicker) view(styles styles, width int) string {
 		b.WriteString(preview + "\n\n")
 	}
 	b.WriteString(strings.Join(wrapText(
-		"A cover hides the threads you have already read. Press x to look under it.",
+		"A cover hides the threads you have already read. Press z to look under it.",
 		contentWidth), "\n"))
 	return b.String()
 }
diff --git a/internal/tui/covers_test.go b/internal/tui/covers_test.go
index 79d438b6..8f087805 100644
--- a/internal/tui/covers_test.go
+++ b/internal/tui/covers_test.go
@@ -556,7 +556,7 @@ func TestCoverHidesPreviouslySeen(t *testing.T) {
 	if !strings.Contains(view, sectionPreviouslySeen.label()) {
 		t.Error("covered list dropped the Previously Seen divider")
 	}
-	if !strings.Contains(view, "3 hidden · x to peek") {
+	if !strings.Contains(view, "3 hidden · z to peek") {
 		t.Error("covered list gave no hint about what is under the cover")
 	}
 	for _, posting := range list.postings[1:] {
@@ -599,7 +599,7 @@ func TestPeekingLiftsTheCover(t *testing.T) {
 	if !strings.Contains(view, list.postings[2].Name) {
 		t.Error("peeking did not reveal the seen threads")
 	}
-	if !strings.Contains(view, "x to cover") {
+	if !strings.Contains(view, "z to cover") {
 		t.Error("a peeked list does not say how to put the cover back")
 	}
 
@@ -627,7 +627,7 @@ func TestCoverDropsTheArtBeforeTheDivider(t *testing.T) {
 	list := coveredList(coverTopo, coverMinRows+2, false, false, true)
 
 	view := list.view()
-	if !strings.Contains(view, "1 hidden · x to peek") {
+	if !strings.Contains(view, "1 hidden · z to peek") {
 		t.Error("a short covered list lost its divider")
 	}
 	if rows := strings.Count(view, "\n") + 1; rows > coverMinRows+2 {
@@ -643,7 +643,7 @@ func TestCoverWithNothingUnread(t *testing.T) {
 		t.Errorf("itemCount = %d, want 0", got)
 	}
 	view := list.view()
-	if !strings.Contains(view, "2 hidden · x to peek") {
+	if !strings.Contains(view, "2 hidden · z to peek") {
 		t.Error("an all-read Imbox does not say what is under the cover")
 	}
 	if rows := strings.Count(view, "\n") + 1; rows != 20 {
diff --git a/internal/tui/mail.go b/internal/tui/mail.go
index 2a634ade..90ab30b1 100644
--- a/internal/tui/mail.go
+++ b/internal/tui/mail.go
@@ -1007,7 +1007,7 @@ func (v *mailView) HelpBindings() []helpBinding {
 		}
 		bindings := []helpBinding{
 			{"enter", "open"},
-			{"space", "select"},
+			{"space/x", "select"},
 			{"ctrl+b", "bulk reply"},
 			{"r", "reply"},
 			{"f", "forward"},
@@ -1044,7 +1044,7 @@ func (v *mailView) HelpBindings() []helpBinding {
 		{"/", "search"},
 		{"ctrl+s", "screener"},
 		{"c", "compose"},
-		{"space", "select"},
+		{"space/x", "select"},
 		{"ctrl+b", "bulk reply"},
 		{"r", "reply"},
 		{"f", "forward"},
@@ -1066,9 +1066,9 @@ func (v *mailView) HelpBindings() []helpBinding {
 		helpBinding{"ctrl+r", "reload"},
 	)
 	if v.postingList.cover != coverNone {
-		peek := helpBinding{"x", "peek under cover"}
+		peek := helpBinding{"z", "peek under cover"}
 		if v.postingList.coverPeeked {
-			peek = helpBinding{"x", "cover"}
+			peek = helpBinding{"z", "cover"}
 		}
 		bindings = append(bindings, peek)
 	}
@@ -1377,7 +1377,7 @@ func (v *mailView) HandleContentKey(msg tea.KeyPressMsg) tea.Cmd {
 			case "j":
 				v.seenList.moveDown()
 				return v.loadMoreSeenPostings()
-			case " ", "space":
+			case " ", "space", "x":
 				v.seenList.toggleSelected()
 				return nil
 			case "ctrl+b":
@@ -1417,7 +1417,7 @@ func (v *mailView) HandleContentKey(msg tea.KeyPressMsg) tea.Cmd {
 			return v.startSearch()
 		case "c":
 			return v.startCompose()
-		case " ", "space":
+		case " ", "space", "x":
 			v.postingList.toggleSelected()
 			return nil
 		case "ctrl+b":
@@ -1431,7 +1431,7 @@ func (v *mailView) HandleContentKey(msg tea.KeyPressMsg) tea.Cmd {
 			return v.startFolderPicker()
 		case "n", "N":
 			return v.startCollectionPicker()
-		case "x":
+		case "z":
 			v.postingList.toggleCoverPeek()
 			return nil
 		case "ctrl+v":
diff --git a/internal/tui/mail_test.go b/internal/tui/mail_test.go
index 8da197f8..54fea5f1 100644
--- a/internal/tui/mail_test.go
+++ b/internal/tui/mail_test.go
@@ -3319,16 +3319,43 @@ func TestMailViewHaystackPickerAliases(t *testing.T) {
 	}
 }
 
-func TestMailViewCoverPeekUsesX(t *testing.T) {
+func TestMailViewCoverPeekUsesZ(t *testing.T) {
 	v := mailWithPostings()
 	v.postingList.setCover(coverTopo)
-	v.HandleContentKey(keyPress("x"))
+	v.HandleContentKey(keyPress("z"))
 	if !v.postingList.coverPeeked {
-		t.Fatal("x did not lift the cover")
+		t.Fatal("z did not lift the cover")
+	}
+	v.HandleContentKey(keyPress("z"))
+	if v.postingList.coverPeeked {
+		t.Fatal("z did not replace the cover")
 	}
+}
+
+// x selects like space does, matching the HEY desktop app — including on a covered
+// Imbox, where x used to lift the cover (that is z's key now).
+func TestMailViewSelectsWithXLikeSpace(t *testing.T) {
+	v := mailWithPostings()
+	v.postingList.setCover(coverTopo)
+
 	v.HandleContentKey(keyPress("x"))
+	if ids := v.postingList.selectedIDs(); len(ids) != 1 || ids[0] != 100 {
+		t.Fatalf("selected after x = %v, want [100]", ids)
+	}
 	if v.postingList.coverPeeked {
-		t.Fatal("x did not replace the cover")
+		t.Error("x lifted the cover instead of selecting")
+	}
+	v.HandleContentKey(keyPress("x"))
+	if ids := v.postingList.selectedIDs(); len(ids) != 0 {
+		t.Errorf("selected after second x = %v, want none", ids)
+	}
+
+	seen := mailWithPostings()
+	seen.seenActive = true
+	seen.seenList.setPostings(testPostings())
+	seen.HandleContentKey(keyPress("x"))
+	if ids := seen.seenList.selectedIDs(); len(ids) != 1 || ids[0] != 100 {
+		t.Errorf("seen screen selected after x = %v, want [100]", ids)
 	}
 }
 
@@ -4269,7 +4296,7 @@ func TestMailViewSeenScreenHelpOffersTheThreadActions(t *testing.T) {
 	v.seenActive = true
 
 	bindings := v.HelpBindings()
-	for _, key := range []string{"enter", "space", "ctrl+b", "a", "l", "u", "t", "v", "b", "n"} {
+	for _, key := range []string{"enter", "space/x", "ctrl+b", "a", "l", "u", "t", "v", "b", "n"} {
 		if !hasHelpBinding(bindings, key) {
 			t.Errorf("seen screen help misses %q: %+v", key, bindings)
 		}