Keep dropdowns right-aligned

main.go

@@ -5672,10 +5672,7 @@ func (u *ui) syncButtonGroup(gtx layout.Context) layout.Dimensions {
 	menuDims := layout.Inset{Top: unit.Dp(6)}.Layout(menuGTX, u.syncMenu)
 	menuCall := menuOps.Stop()
 
-	menuX := rowDims.Size.X - menuDims.Size.X
-	if menuX < 0 {
-		menuX = 0
-	}
+	menuX := anchoredMenuX(rowDims.Size.X, menuDims.Size.X)
 	stack := op.Offset(image.Pt(menuX, rowDims.Size.Y)).Push(gtx.Ops)
 	menuCall.Add(gtx.Ops)
 	stack.Pop()
@@ -7198,10 +7195,7 @@ func (u *ui) mainMenuButtonGroup(gtx layout.Context) layout.Dimensions {
 	menuDims := layout.Inset{Top: unit.Dp(6)}.Layout(menuGTX, u.mainMenu)
 	menuCall := menuOps.Stop()
 
-	menuX := buttonDims.Size.X - menuDims.Size.X
-	if menuX < 0 {
-		menuX = 0
-	}
+	menuX := anchoredMenuX(buttonDims.Size.X, menuDims.Size.X)
 	stack := op.Offset(image.Pt(menuX, buttonDims.Size.Y)).Push(gtx.Ops)
 	menuCall.Add(gtx.Ops)
 	stack.Pop()
@@ -7224,6 +7218,10 @@ func (u *ui) mainMenuRightAlignsToTrigger() bool {
 	return true
 }
 
+func anchoredMenuX(triggerWidth, menuWidth int) int {
+	return triggerWidth - menuWidth
+}
+
 func detailLine(th *material.Theme, label, value string) layout.Widget {
 	return func(gtx layout.Context) layout.Dimensions {
 		valueSize := unit.Sp(16)

main_test.go

@@ -356,6 +356,17 @@ func TestUIMainMenuAnchorsMatchAcrossModes(t *testing.T) {
 	}
 }
 
+func TestAnchoredMenuXAllowsWiderMenusToExtendLeft(t *testing.T) {
+	t.Parallel()
+
+	if got := anchoredMenuX(48, 160); got != -112 {
+		t.Fatalf("anchoredMenuX(48, 160) = %d, want -112", got)
+	}
+	if got := anchoredMenuX(160, 48); got != 112 {
+		t.Fatalf("anchoredMenuX(160, 48) = %d, want 112", got)
+	}
+}
+
 func TestUICurrentVaultSummary(t *testing.T) {
 	t.Parallel()