diff --git a/CHANGELOG.md b/CHANGELOG.md
index bf29823..393f650 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -42,6 +42,11 @@ All notable changes to Jarl are documented here. The format follows
 
 ### Changed
 
+- `cname_chain` no longer warns about one CNAME pointing at another (a
+  service name at a host alias is common, and named answers the chain at
+  once). A chain of three or more CNAMEs gets an info note that shows
+  it.
+
 - A certificate's private key is only exported over HTTPS, the local
   socket, or to the server itself (plain HTTP from another host is
   refused with `https_required`).
@@ -70,6 +75,10 @@ All notable changes to Jarl are documented here. The format follows
 
 ### Fixed
 
+- The statistics' "Busiest times" grid drew hours without data taller
+  than the others (they picked up the page's padding for empty
+  messages).
+
 - A token for one view of a linked zone (such as an ACME token with
   `views=external`) couldn't add records: a new record is shared, and
   that reached the other view. A new name and type is now local to the
diff --git a/docs/validation.md b/docs/validation.md
index 21e4923..1d644a6 100644
--- a/docs/validation.md
+++ b/docs/validation.md
@@ -34,7 +34,7 @@ showing them.
 | `cname_multiple` | error | A name can have only one CNAME |
 | `cname_apex` | error | No CNAME at the zone apex (it needs SOA and NS) |
 | `cname_loop` | error | CNAMEs that point back to themselves |
-| `cname_chain` | warning | CNAME to a CNAME: works, but slows resolution |
+| `cname_chain` | info | a chain of three or more CNAMEs (one CNAME to another says nothing): works, but each is another lookup for some resolvers |
 | `cname_dangling` | warning | CNAME to a name that doesn't exist in the zone |
 | `dname_multiple`, `below_dname` | error | One DNAME per name, and nothing below a DNAME (RFC 6672) |
 | `apex_ns_missing` | error | A zone needs NS records at its apex |
diff --git a/internal/validate/records.go b/internal/validate/records.go
index 03bcd08..66fd9a1 100644
--- a/internal/validate/records.go
+++ b/internal/validate/records.go
@@ -385,8 +385,16 @@ func (c *checker) checkCNAMETarget(z *model.Zone, ix *zoneIndex, r *model.Record
 	if !ix.inZoneTarget(target) {
 		return
 	}
-	// Follow the chain inside the zone to detect loops.
+	// Follow the chain inside the zone to detect loops. One CNAME to
+	// another is common and costs nothing (named answers the chain in
+	// one response); a longer chain gets a note.
 	seen := map[string]bool{r.Name: true}
+	chain := []string{disp(r.Name), disp(target)}
+	note := func() {
+		if len(chain) > 3 {
+			c.recProblem(z, r, Info, "cname_chain", "%s reaches its address through %d CNAMEs (%s); fine, but each one is another lookup for resolvers that don't get the chain at once", disp(r.Name), len(chain)-1, strings.Join(chain, " → "))
+		}
+	}
 	cur := target
 	for hops := 0; hops < 20; hops++ {
 		if seen[cur] {
@@ -398,18 +406,18 @@ func (c *checker) checkCNAMETarget(z *model.Zone, ix *zoneIndex, r *model.Record
 		if len(next) == 0 {
 			break
 		}
-		if hops == 0 {
-			c.recProblem(z, r, Warning, "cname_chain", "%s is a CNAME to %s, which is itself a CNAME; chains slow down resolution", disp(r.Name), disp(target))
-		}
 		p := ix.parsed[next[0].ID]
 		if p == nil {
 			break
 		}
 		cur = p.RR.(*dns.CNAME).Target
+		chain = append(chain, disp(cur))
 		if !ix.inZoneTarget(cur) {
+			note()
 			return
 		}
 	}
+	note()
 	if len(ix.byName[target]) == 0 && !ix.hasAddress(target) && !hasDescendant(ix, target) {
 		c.recProblem(z, r, Warning, "cname_dangling", "%s is a CNAME to %s, which does not exist in the zone", disp(r.Name), disp(target))
 	}
diff --git a/internal/validate/validate_test.go b/internal/validate/validate_test.go
index df74447..92d9180 100644
--- a/internal/validate/validate_test.go
+++ b/internal/validate/validate_test.go
@@ -161,8 +161,9 @@ func TestRecordConflicts(t *testing.T) {
 		}, "cname_loop", Error},
 		{"cname chain", func(b *builder, z *model.Zone) {
 			b.rec(z, "a", "CNAME", "b")
-			b.rec(z, "b", "CNAME", "ns1")
-		}, "cname_chain", Warning},
+			b.rec(z, "b", "CNAME", "c")
+			b.rec(z, "c", "CNAME", "ns1")
+		}, "cname_chain", Info},
 		{"dangling cname", func(b *builder, z *model.Zone) { b.rec(z, "a", "CNAME", "nothing") }, "cname_dangling", Warning},
 		{"null mx not alone", func(b *builder, z *model.Zone) {
 			b.rec(z, "@", "MX", "0 .")
@@ -380,3 +381,16 @@ func TestProblemStringDisplaysZone(t *testing.T) {
 		t.Errorf("String() = %q, want %q", got, want)
 	}
 }
+
+// One CNAME to another is common and says nothing.
+func TestShortCNAMEChain(t *testing.T) {
+	b := newBuilder()
+	z := b.primary("example.com", nil)
+	b.rec(z, "songshare", "CNAME", "navidrome")
+	b.rec(z, "navidrome", "CNAME", "ns1")
+	for _, p := range State(b.s, Options{}) {
+		if p.Code == "cname_chain" {
+			t.Errorf("one extra CNAME: %s %s", p.Severity, p.Message)
+		}
+	}
+}
diff --git a/internal/web/static/assets/charts.js b/internal/web/static/assets/charts.js
index 0624035..4960989 100644
--- a/internal/web/static/assets/charts.js
+++ b/internal/web/static/assets/charts.js
@@ -283,7 +283,7 @@ export function heatmap(hm, unit) {
       const n = hm.samples[d][hr];
       const text = v < 0 ? day + " " + pad(hr) + ":00 – no data" :
         day + " " + pad(hr) + ":00 – " + Math.round(v).toLocaleString() + " " + unit + " per hour (average of " + n + (n === 1 ? " hour)" : " hours)");
-      const cell = h("div", { class: "hm-cell " + (v < 0 ? "empty" : "heat-" + level(v)), tabindex: "-1", "aria-label": text });
+      const cell = h("div", { class: "hm-cell " + (v < 0 ? "hm-empty" : "heat-" + level(v)), tabindex: "-1", "aria-label": text });
       const showTip = () => {
         tip.textContent = text;
         tip.hidden = false;
@@ -313,7 +313,7 @@ export function heatmap(hm, unit) {
     h("span", { class: "muted small" }, "0"),
     Array.from({ length: steps }, (_, i) => h("span", { class: "hm-swatch heat-" + i })),
     h("span", { class: "muted small" }, compact(peak) + " " + unit + "/hour"),
-    h("span", { class: "hm-swatch empty" }), h("span", { class: "muted small" }, "no data"));
+    h("span", { class: "hm-swatch hm-empty" }), h("span", { class: "muted small" }, "no data"));
   return h("div", { class: "heatmap-wrap" }, grid, tip, scale);
 }
 
diff --git a/internal/web/static/assets/style.css b/internal/web/static/assets/style.css
index c6fa914..9082304 100644
--- a/internal/web/static/assets/style.css
+++ b/internal/web/static/assets/style.css
@@ -398,7 +398,7 @@ td.num, th.num { text-align: right; font-variant-numeric: tabular-nums; }
 .hm-row { display: flex; align-items: center; }
 .hm-cell { height: 22px; border-radius: 3px; }
 .hm-cell:hover, .hm-cell:focus { outline: 2px solid var(--text); outline-offset: -1px; }
-.hm-cell.empty, .hm-swatch.empty { background: transparent; box-shadow: inset 0 0 0 1px var(--chart-grid); }
+.hm-empty { background: transparent; box-shadow: inset 0 0 0 1px var(--chart-grid); }
 .heat-0 { background: var(--heat-0); } .heat-1 { background: var(--heat-1); } .heat-2 { background: var(--heat-2); }
 .heat-3 { background: var(--heat-3); } .heat-4 { background: var(--heat-4); } .heat-5 { background: var(--heat-5); }
 .heat-6 { background: var(--heat-6); }