diff --git a/internal/ui/shell.go b/internal/ui/shell.go
index cfc1baf..7ac22f6 100644
--- a/internal/ui/shell.go
+++ b/internal/ui/shell.go
@@ -160,6 +160,7 @@ func NewShell(theme *material.Theme) *Shell {
 	s.logDir.SetText(`C:\Users\Public\chub\logs`)
 	s.closeOnExit.Value = true
 	s.browserKind.Value = "chrome"
+	s.list.Axis = layout.Vertical
 	return s
 }
 
diff --git a/internal/ui/shell_test.go b/internal/ui/shell_test.go
index becaba3..ce7ee7b 100644
--- a/internal/ui/shell_test.go
+++ b/internal/ui/shell_test.go
@@ -5,6 +5,7 @@ import (
 	"testing"
 	"time"
 
+	"gioui.org/layout"
 	"gioui.org/widget/material"
 )
 
@@ -21,6 +22,13 @@ func TestShellStartsWithSemanticInstanceStatuses(t *testing.T) {
 	}
 }
 
+func TestShellInstanceListScrollsVertically(t *testing.T) {
+	shell := NewShell(material.NewTheme())
+	if shell.list.Axis != layout.Vertical {
+		t.Fatalf("instance list axis = %v, want vertical", shell.list.Axis)
+	}
+}
+
 func TestShellInstanceRowsContainRequiredColumnsAndIndependentActionControls(t *testing.T) {
 	shell := NewShell(material.NewTheme())
 	if len(shell.rows) < 2 {