diff --git a/CotEditor/Sources/AboutView.swift b/CotEditor/Sources/AboutView.swift
index 071cda77d..d9cd2a1be 100644
--- a/CotEditor/Sources/AboutView.swift
+++ b/CotEditor/Sources/AboutView.swift
@@ -255,7 +255,7 @@ private struct CreditsView: View {
         var content: () -> Content
         
         
-        init(_ label: String, content: @escaping () -> Content) {
+        init(_ label: String, @ViewBuilder content: @escaping () -> Content) {
             
             self.label = label
             self.content = content
diff --git a/CotEditor/Sources/PopoverHolderView.swift b/CotEditor/Sources/PopoverHolderView.swift
index 233e3e7d5..d7bd3d1ea 100644
--- a/CotEditor/Sources/PopoverHolderView.swift
+++ b/CotEditor/Sources/PopoverHolderView.swift
@@ -51,11 +51,11 @@ private extension Edge {
 }
 
 
-private struct PopoverHolderView<T: View>: NSViewRepresentable {
+private struct PopoverHolderView<Content: View>: NSViewRepresentable {
     
     @Binding var isPresented: Bool
     let arrowEdge: Edge
-    var content: () -> T
+    @ViewBuilder var content: () -> Content
     
     
     func makeNSView(context: Context) -> NSView {
diff --git a/CotEditor/Sources/SyntaxFileMappingEditView.swift b/CotEditor/Sources/SyntaxFileMappingEditView.swift
index f7408fe74..916dc4043 100644
--- a/CotEditor/Sources/SyntaxFileMappingEditView.swift
+++ b/CotEditor/Sources/SyntaxFileMappingEditView.swift
@@ -78,7 +78,7 @@ struct SyntaxFileMappingEditView: View {
         
         
         @Binding var items: [Item]
-        let label: () -> (Label)
+        let label: () -> Label
         
         @State private var selection: Set<Item.ID> = []
         @FocusState private var focusedField: Item.ID?
diff --git a/CotEditor/Sources/WrappingHStack.swift b/CotEditor/Sources/WrappingHStack.swift
index e6d210f42..7c1fbb82b 100644
--- a/CotEditor/Sources/WrappingHStack.swift
+++ b/CotEditor/Sources/WrappingHStack.swift
@@ -29,7 +29,7 @@ struct WrappingHStack<Content: View>: View {
     
     var horizontalSpacing: Double = 4
     var verticalSpacing: Double = 4
-    var content: () -> Content
+    @ViewBuilder var content: () -> Content
     
     
     var body: some View {