diff --git a/Mastodon/Diffiable/Section/ComposeStatusSection.swift b/Mastodon/Diffiable/Section/ComposeStatusSection.swift
index e9785461a..ebf95a093 100644
--- a/Mastodon/Diffiable/Section/ComposeStatusSection.swift
+++ b/Mastodon/Diffiable/Section/ComposeStatusSection.swift
@@ -22,6 +22,7 @@ enum ComposeStatusSection: Equatable, Hashable {
 extension ComposeStatusSection {
     enum ComposeKind {
         case post
+        case mention(mastodonUserObjectID: NSManagedObjectID)
         case reply(repliedToStatusObjectID: NSManagedObjectID)
     }
 }
diff --git a/Mastodon/Helper/MastodonField.swift b/Mastodon/Helper/MastodonField.swift
index cbe87c09b..e828602e4 100644
--- a/Mastodon/Helper/MastodonField.swift
+++ b/Mastodon/Helper/MastodonField.swift
@@ -11,7 +11,7 @@ import ActiveLabel
 enum MastodonField {
     
     static func parse(field string: String) -> ParseResult {
-        let mentionMatches = string.matches(pattern: "(?:@([a-zA-Z0-9_]+))")
+        let mentionMatches = string.matches(pattern: "(?:@([a-zA-Z0-9_]+)(@[a-zA-Z0-9_.]+)?)")
         let hashtagMatches = string.matches(pattern: "(?:#([^\\s.]+))")
         let urlMatches = string.matches(pattern: "(?i)https?://\\S+(?:/|\\b)")
         
diff --git a/Mastodon/Scene/Compose/ComposeViewController.swift b/Mastodon/Scene/Compose/ComposeViewController.swift
index c316e993e..3e82cd51a 100644
--- a/Mastodon/Scene/Compose/ComposeViewController.swift
+++ b/Mastodon/Scene/Compose/ComposeViewController.swift
@@ -538,7 +538,7 @@ extension ComposeViewController: TextEditorViewTextAttributesDelegate {
             os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s: update: %s", ((#file as NSString).lastPathComponent), #line, #function, string)
 
             let stringRange = NSRange(location: 0, length: string.length)
-            let highlightMatches = string.matches(pattern: "(?:@([a-zA-Z0-9_]+)|#([^\\s.]+))")
+            let highlightMatches = string.matches(pattern: "(?:@([a-zA-Z0-9_]+)(@[a-zA-Z0-9_.]+)?|#([^\\s.]+))")
             // accept ^\B: or \s: but not accept \B: to force user input a space to make emoji take effect
             // precondition :\B with following space 
             let emojiMatches = string.matches(pattern: "(?:(^\\B:|\\s:)([a-zA-Z0-9_]+)(:\\B(?=\\s)))")
diff --git a/Mastodon/Scene/Compose/ComposeViewModel+Diffable.swift b/Mastodon/Scene/Compose/ComposeViewModel+Diffable.swift
index d44892565..496ba2845 100644
--- a/Mastodon/Scene/Compose/ComposeViewModel+Diffable.swift
+++ b/Mastodon/Scene/Compose/ComposeViewModel+Diffable.swift
@@ -62,7 +62,7 @@ extension ComposeViewModel {
         case .reply(let statusObjectID):
             snapshot.appendItems([.replyTo(statusObjectID: statusObjectID)], toSection: .repliedTo)
             snapshot.appendItems([.input(replyToStatusObjectID: statusObjectID, attribute: composeStatusAttribute)], toSection: .repliedTo)
-        case .post:
+        case .mention, .post:
             snapshot.appendItems([.input(replyToStatusObjectID: nil, attribute: composeStatusAttribute)], toSection: .status)
         }
         diffableDataSource.apply(snapshot, animatingDifferences: false)
diff --git a/Mastodon/Scene/Compose/ComposeViewModel.swift b/Mastodon/Scene/Compose/ComposeViewModel.swift
index 52ca4cc88..3b81a931c 100644
--- a/Mastodon/Scene/Compose/ComposeViewModel.swift
+++ b/Mastodon/Scene/Compose/ComposeViewModel.swift
@@ -71,18 +71,27 @@ final class ComposeViewModel {
     
     init(
         context: AppContext,
-        composeKind: ComposeStatusSection.ComposeKind
+        composeKind: ComposeStatusSection.ComposeKind,
+        initialComposeContent: String? = nil
     ) {
         self.context = context
         self.composeKind = composeKind
         switch composeKind {
-        case .post:         self.title = CurrentValueSubject(L10n.Scene.Compose.Title.newPost)
-        case .reply:        self.title = CurrentValueSubject(L10n.Scene.Compose.Title.newReply)
+        case .post, .mention:       self.title = CurrentValueSubject(L10n.Scene.Compose.Title.newPost)
+        case .reply:                self.title = CurrentValueSubject(L10n.Scene.Compose.Title.newReply)
         }
         self.activeAuthentication = CurrentValueSubject(context.authenticationService.activeMastodonAuthentication.value)
         self.activeAuthenticationBox = CurrentValueSubject(context.authenticationService.activeMastodonAuthenticationBox.value)
         // end init
         
+        if case let .mention(mastodonUserObjectID) = composeKind {
+            context.managedObjectContext.performAndWait {
+                let mastodonUser = context.managedObjectContext.object(with: mastodonUserObjectID) as! MastodonUser
+                let initialComposeContent = "@" + mastodonUser.acct + " "
+                self.composeStatusAttribute.composeContent.value = initialComposeContent
+            }
+        }
+        
         isCustomEmojiComposing
             .assign(to: \.value, on: customEmojiPickerInputViewModel.isCustomEmojiComposing)
             .store(in: &disposeBag)
diff --git a/Mastodon/Scene/Profile/ProfileViewController.swift b/Mastodon/Scene/Profile/ProfileViewController.swift
index 57a398b4b..315a49427 100644
--- a/Mastodon/Scene/Profile/ProfileViewController.swift
+++ b/Mastodon/Scene/Profile/ProfileViewController.swift
@@ -429,7 +429,12 @@ extension ProfileViewController {
     
     @objc private func replyBarButtonItemPressed(_ sender: UIBarButtonItem) {
         os_log(.info, log: .debug, "%{public}s[%{public}ld], %{public}s", ((#file as NSString).lastPathComponent), #line, #function)
-        // TODO:
+        guard let mastodonUser = viewModel.mastodonUser.value else { return }
+        let composeViewModel = ComposeViewModel(
+            context: context,
+            composeKind: .mention(mastodonUserObjectID: mastodonUser.objectID)
+        )
+        coordinator.present(scene: .compose(viewModel: composeViewModel), from: self, transition: .modal(animated: true, completion: nil))
     }
     
     @objc private func refreshControlValueChanged(_ sender: UIRefreshControl) {
@@ -641,7 +646,7 @@ extension ProfileViewController: ProfileHeaderViewDelegate {
     }
     
     func profileHeaderView(_ profileHeaderView: ProfileHeaderView, profileStatusDashboardView: ProfileStatusDashboardView, postDashboardMeterViewDidPressed dashboardMeterView: ProfileStatusDashboardMeterView) {
-        
+
     }
     
     func profileHeaderView(_ profileHeaderView: ProfileHeaderView, profileStatusDashboardView: ProfileStatusDashboardView, followingDashboardMeterViewDidPressed dwingDashboardMeterView: ProfileStatusDashboardMeterView) {