diff --git a/.claude/CLAUDE.md b/.claude/CLAUDE.md
index 146908a..0405f42 100644
--- a/.claude/CLAUDE.md
+++ b/.claude/CLAUDE.md
@@ -121,6 +121,12 @@ markup for it. The one that has already bitten us:
   this; it parses the templates structurally, so extend it there if you find
   another flex-container component with the same trap.
 
+- **A `<button>` centers its text.** Invisible on a normal button, wrong the
+  moment you use one as a full-width row (`d-flex w-100`, e.g. a `list-group-item`
+  that expands a collapse): the label sits centered while every neighboring row is
+  left-aligned. **Add `text-start`.** `TestFullWidthFlexButtonsAreTextStart`, in
+  the same file, enforces it.
+
 ### 5. CI is the gate, not the first line
 Woodpecker (`.woodpecker/`): `test` + `lint` + `vuln` (govulncheck) must pass
 before `build`; `deploy` follows `build` on `main`. A reachable CVE blocks the
diff --git a/internal/marketing/templates/user_public.html b/internal/marketing/templates/user_public.html
index 6d309ad..a47deb2 100644
--- a/internal/marketing/templates/user_public.html
+++ b/internal/marketing/templates/user_public.html
@@ -39,7 +39,10 @@
         {{range $i, $l := .Links}}
         {{if $l.IsMeshCore}}
         <div class="list-group-item">
-          <button type="button" class="d-flex align-items-center gap-2 text-reset border-0 bg-transparent p-0 w-100" data-bs-toggle="collapse" data-bs-target="#mesh-{{$i}}" aria-expanded="false" aria-controls="mesh-{{$i}}">
+          {{/* text-start because this row is a <button>, and a button centers its
+               text by default — without it this one label sits centered while every
+               other row in the list is left-aligned. */}}
+          <button type="button" class="d-flex align-items-center gap-2 text-reset text-start border-0 bg-transparent p-0 w-100" data-bs-toggle="collapse" data-bs-target="#mesh-{{$i}}" aria-expanded="false" aria-controls="mesh-{{$i}}">
             <span class="text-secondary d-flex" title="{{$l.PlatformName}}">{{template "link-icon" $l.Platform}}</span>
             <span class="flex-fill text-truncate">{{$l.Display}}</span>
             <span class="text-secondary d-flex">{{template "icon-qrcode" ""}}</span>
diff --git a/internal/web/alert_layout_test.go b/internal/web/alert_layout_test.go
index a37a22f..5030709 100644
--- a/internal/web/alert_layout_test.go
+++ b/internal/web/alert_layout_test.go
@@ -76,6 +76,56 @@ func TestAlertBodiesAreSingleChild(t *testing.T) {
 	}
 }
 
+// TestFullWidthFlexButtonsAreTextStart is the same class of trap as
+// TestAlertBodiesAreSingleChild: a component whose default styling quietly
+// contradicts the layout it's being used for.
+//
+// A <button> centers its text. That's invisible on an ordinary button, whose text
+// is the whole content — but a full-width button used as a row (d-flex + w-100,
+// e.g. the MeshCore key row in the public profile's Links list) inherits that
+// centering into every child, so its label floats in the middle of the row while
+// every neighboring row is left-aligned. Nothing errors; it just looks wrong next
+// to the rows around it.
+//
+// The fix is always the same: add text-start.
+func TestFullWidthFlexButtonsAreTextStart(t *testing.T) {
+	t.Parallel()
+	root := moduleRoot(t)
+
+	// Buttons only: an <a> or <div> laid out the same way already inherits the
+	// page's left alignment. w-100 scopes this to buttons acting as rows.
+	buttonRe := regexp.MustCompile(`(?is)<button[^>]*class="([^"]*)"[^>]*>`)
+
+	err := filepath.WalkDir(filepath.Join(root, "internal"), func(path string, d os.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if d.IsDir() || !strings.HasSuffix(path, ".html") {
+			return nil
+		}
+		b, err := os.ReadFile(path)
+		if err != nil {
+			return err
+		}
+		rel, _ := filepath.Rel(root, path)
+		for _, m := range buttonRe.FindAllSubmatch(b, -1) {
+			classes := map[string]bool{}
+			for _, c := range strings.Fields(string(m[1])) {
+				classes[c] = true
+			}
+			if classes["d-flex"] && classes["w-100"] && !classes["text-start"] {
+				t.Errorf("%s: full-width flex <button> is missing text-start — a button "+
+					"centers its text, so this row's label sits centered while the rows "+
+					"around it are left-aligned. Found class=%q", rel, m[1])
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		t.Fatalf("walk templates: %v", err)
+	}
+}
+
 // findAlerts returns every element carrying the bare "alert" class. Modifier
 // classes (alert-title, alert-icon, alert-heading) are not flex containers and
 // are deliberately excluded.