diff --git a/src/mail/boxes.rs b/src/mail/boxes.rs
index 20bfb4c..fa780f9 100644
--- a/src/mail/boxes.rs
+++ b/src/mail/boxes.rs
@@ -152,7 +152,9 @@ impl RenderOnce for MailboxList {
                 .iter()
                 .flat_map(|(_, boxes)| boxes)
                 .any(|mailbox| mailbox.key == *open);
-            assert!(listed, "no mailbox {open}");
+            if !listed {
+                log::error!("mailbox list: no mailbox {open}; none open");
+            }
         }
         let open: OnValue = {
             let (id, on_open) = (self.id.clone(), self.on_open.clone());
diff --git a/src/mail/labels.rs b/src/mail/labels.rs
index 3fddfac..1c6a3c1 100644
--- a/src/mail/labels.rs
+++ b/src/mail/labels.rs
@@ -120,7 +120,12 @@ impl RenderOnce for LabelPicker {
     fn render(self, window: &mut Window, cx: &mut App) -> impl IntoElement {
         for key in &self.selected {
             let known = self.labels.iter().any(|label| label.key == *key);
-            assert!(known, "label picker {:?}: no label {key}", self.id);
+            if !known {
+                log::error!(
+                    "label picker {:?}: no label {key}; it is not ticked",
+                    self.id
+                );
+            }
         }
         let finding = window.use_keyed_state(
             (self.id.clone(), "finding"),
diff --git a/src/mail/list.rs b/src/mail/list.rs
index 9dbd0b1..23d3e9e 100644
--- a/src/mail/list.rs
+++ b/src/mail/list.rs
@@ -284,7 +284,9 @@ impl RenderOnce for MailList {
     fn render(self, _: &mut Window, cx: &mut App) -> impl IntoElement {
         for key in &self.selected {
             let listed = self.mails.iter().any(|mail| mail.key == *key);
-            assert!(listed, "no mail {key}");
+            if !listed {
+                log::error!("mail list: no mail {key}; it is not selected");
+            }
         }
         let theme = cx.theme();
         if self.mails.is_empty() {
diff --git a/src/mail/tests/sort.rs b/src/mail/tests/sort.rs
index 4bccac4..9af64fb 100644
--- a/src/mail/tests/sort.rs
+++ b/src/mail/tests/sort.rs
@@ -128,12 +128,21 @@ fn a_label_name_is_listed_once() {
 }
 
 #[gpui::test]
-#[should_panic(expected = "no label ghost")]
-fn what_is_on_is_a_label(cx: &mut TestAppContext) {
+fn a_label_mail_or_box_that_left_draws_unmarked(cx: &mut TestAppContext) {
     let _ = mailing(
         |_| {
-            LabelPicker::new("labels", [Label::new("a", "A", 0)])
-                .selected(["ghost"])
+            let mail = crate::mail::Mail::new("m1", "Ada", "Plans", Timestamp::UNIX_EPOCH);
+            let inbox =
+                crate::mail::Mailbox::new("inbox", "Inbox", crate::primitives::IconName::Inbox);
+            div()
+                .w(px(480.0))
+                .child(LabelPicker::new("labels", [Label::new("a", "A", 0)]).selected(["ghost"]))
+                .child(crate::mail::MailList::new("mails", [mail]).selected(["gone"]))
+                .child(
+                    crate::mail::MailboxList::new("boxes")
+                        .section("Mail", [inbox])
+                        .open("gone"),
+                )
                 .into_any_element()
         },
         cx,
diff --git a/src/mail/times.rs b/src/mail/times.rs
index 42e79e9..7cb234a 100644
--- a/src/mail/times.rs
+++ b/src/mail/times.rs
@@ -40,12 +40,15 @@ pub(super) fn named(name: &str, at: Timestamp, zone: &TimeZone) -> (String, Time
     (format!("{name} · {hour}"), at)
 }
 
-/// The moment `chosen` names in `zone`, once it lies after `now`.
+/// The moment `chosen` names in `zone`, once it lies after `now`; none past the times jiff holds.
 pub(super) fn ahead(chosen: DateTime, zone: &TimeZone, now: Timestamp) -> Option<Timestamp> {
-    let at = chosen
-        .to_zoned(zone.clone())
-        .expect("the zone holds the time")
-        .timestamp();
+    let at = match chosen.to_zoned(zone.clone()) {
+        Ok(at) => at.timestamp(),
+        Err(error) => {
+            log::error!("time dialog: {chosen} has no moment in its zone: {error}");
+            return None;
+        }
+    };
     (at > now).then_some(at)
 }
 
@@ -197,5 +200,11 @@ mod tests {
             None,
             "10:00 in Tokyo is 01:00 here"
         );
+        let west = TimeZone::fixed(offset(-9));
+        assert_eq!(
+            ahead(jiff::civil::DateTime::MAX, &west, now),
+            None,
+            "past what jiff holds"
+        );
     }
 }
diff --git a/tasks/panics.md b/tasks/panics.md
index ccdfc64..5920aa8 100644
--- a/tasks/panics.md
+++ b/tasks/panics.md
@@ -43,7 +43,7 @@ Each item reads every site in its folders, fixes what the rules name, updates ca
 - [x] P26 Media — `src/media`
 - [x] P27 Files — `src/files`
 - [x] P28 Messaging — `src/messaging`
-- [ ] P29 Mail — `src/mail`
+- [x] P29 Mail — `src/mail`
 - [ ] P30 Calendar — `src/calendar`
 - [ ] P31 Project — `src/project`
 - [ ] P32 Canvas & Design — `src/canvas`
@@ -94,3 +94,4 @@ One line per item: what changed, what stayed and why, review rounds.
 - P26: a live position past its media logs and sits at the end (`media::played`); loaded time, a trim and chapters past the length peg or stay out; a gone device or track, or a refused trim, leaves none and clears the last; a dropped root path shows whole; subtitle times no clock holds read as none; a rail layout left no width gives no share (`scrubber::along`), so hover, press and drag skip it; waveform buckets count in `u64`, which a 32-bit web `usize` outgrows. Kept: non-zero lengths, one-value contracts, one list's uniqueness and order, lookups by construction. Review: 4 rounds; it also passed P25's last fix.
 - P27: an owner's pick gone from a grid, an explorer folder or a directory listing logs and is kept as given, so it replaces a local pick and marks none (P13's listing now does the same); the columns mark a path name only while its parent holds it as a folder; moved bytes past a total log, the bar already capped; duplicate marks on no copy, or on every copy of a group, are dropped, so Remove never takes a group's last copy. Kept: one list's uniqueness, a snapshot's path and levels, items and downloads, lookups by construction, `datetime` with a constant pattern. Review: 3 rounds.
 - P28: an open chat or selected member no longer listed logs and marks none. Kept: one list's uniqueness and non-emptiness, one message's receipt and replies, constant `datetime` patterns, picks from lists without disabled rows, keys from the same render. Review: 1 round.
+- P29: an open mailbox, ticked label or selected mail no longer listed logs and marks none; a picked moment its zone cannot hold logs and reads as none, so the time dialog's action stays off. Kept: one list's uniqueness, day arithmetic from the owner's now, constant `datetime` patterns, the dialog's action behind its disabled button. Review: 1 round.