1 files changed, 18 insertions, 8 deletions

diff --git a/gui/internal/ui/forms.go b/gui/internal/ui/forms.go
index 18a8b13..fd97546 100644
--- a/gui/internal/ui/forms.go
+++ b/gui/internal/ui/forms.go
@@ -386,7 +386,7 @@ func (r *settingRow) set(args string) {
 
 // formLabel is one line of the list: what the form is, and what it does.
 func formLabel(f model.Form) string {
-	if f.Kind == model.ExcludeForm {
+	if f.Kind == model.ExcludeForm || f.Rule == nil {
 		return "exclude: " + f.Label
 	}
 	var what []string
@@ -677,7 +677,7 @@ func newFormEditor(form model.Form, changed func()) *formEditor {
 	fe.root.SetMarginTop(6)
 	fe.root.SetMarginBottom(6)
 
-	if form.Kind == model.RuleForm {
+	if form.Kind == model.RuleForm && form.Rule != nil {
 		fe.name = gtk.NewEntry()
 		fe.name.SetText(form.Rule.Name)
 		fe.name.SetHExpand(true)
@@ -692,18 +692,25 @@ func newFormEditor(form model.Form, changed func()) *formEditor {
 		fe.conditions = append(fe.conditions, &model.Cond{Kind: kind})
 	})))
 
-	when := form.Rule.When
-	if form.Kind == model.ExcludeForm {
-		when = form.Exclude.When
-	} else if !form.Rule.HasWhen {
-		when = nil
+	// An exclude has no rule behind it and a rule may have no (when ...) at
+	// all, so neither pointer is followed without asking first: reading
+	// form.Rule for an exclude crashed the window (found by the release
+	// checklist, 2026-09-17).
+	var when []*sexp.Node
+	switch {
+	case form.Kind == model.ExcludeForm:
+		if form.Exclude != nil {
+			when = form.Exclude.When
+		}
+	case form.Rule != nil && form.Rule.HasWhen:
+		when = form.Rule.When
 	}
 	for _, c := range when {
 		fe.conditions = append(fe.conditions, model.ParseCond(c))
 	}
 	fe.drawConds()
 
-	if form.Kind == model.RuleForm {
+	if form.Kind == model.RuleForm && form.Rule != nil {
 		fe.acts = gtk.NewBox(gtk.OrientationVertical, 4)
 		fe.root.Append(heading("Actions - in order"))
 		fe.root.Append(fe.acts)
@@ -756,6 +763,9 @@ func (fe *formEditor) text() (string, error) {
 		}
 		return config.PrintExclude(&config.Exclude{When: when}), nil
 	}
+	if fe.name == nil || fe.stop == nil {
+		return "", fmt.Errorf("this form has no rule behind it")
+	}
 	rule := &config.Rule{
 		Name:    fe.name.Text(),
 		HasWhen: len(when) > 0,