diff --git a/SignalShareExtension/SAEScreenLockViewController.swift b/SignalShareExtension/SAEScreenLockViewController.swift
index d2286947ad..389ba2e9d5 100644
--- a/SignalShareExtension/SAEScreenLockViewController.swift
+++ b/SignalShareExtension/SAEScreenLockViewController.swift
@@ -6,7 +6,7 @@
 import SignalServiceKit
 import SignalUI
 
-final class SAEScreenLockViewController: ScreenLockViewController {
+final class SAEScreenLockViewController: ScreenLockViewController, ScreenLockViewDelegate {
 
     private var completion: ((_ didUnlock: Bool) -> Void)?
 
@@ -28,10 +28,11 @@ final class SAEScreenLockViewController: ScreenLockViewController {
 
     // MARK: - UIViewController
 
-    override func loadView() {
-        super.loadView()
-        view.backgroundColor = Theme.launchScreenBackgroundColor
+    override func viewDidLoad() {
+        super.viewDidLoad()
+
         title = OWSLocalizedString("SHARE_EXTENSION_VIEW_TITLE", comment: "Title for the 'share extension' view.")
+
         navigationItem.leftBarButtonItem = .systemItem(.stop) { [weak self] in
             Logger.debug("tapped dismiss share button")
             self?.cancelShareExperience()
@@ -49,7 +50,7 @@ final class SAEScreenLockViewController: ScreenLockViewController {
 
         ensureUI()
 
-        if !hasShownAuthUIOnce {
+        if hasShownAuthUIOnce == false {
             hasShownAuthUIOnce = true
             tryToPresentAuthUIToUnlockScreenLock()
         }
@@ -66,9 +67,8 @@ final class SAEScreenLockViewController: ScreenLockViewController {
     }
 
     private func tryToPresentAuthUIToUnlockScreenLock() {
-        AssertIsOnMainThread()
+        guard isShowingAuthUI == false else { return }
 
-        guard !isShowingAuthUI else { return }
         isShowingAuthUI = true
 
         ScreenLock.shared.tryToUnlockScreenLock(
@@ -117,8 +117,6 @@ final class SAEScreenLockViewController: ScreenLockViewController {
     }
 
     private func showScreenLockFailureAlertWithMessage(_ message: String) {
-        AssertIsOnMainThread()
-
         OWSActionSheets.showActionSheet(
             title: OWSLocalizedString(
                 "SCREEN_LOCK_UNLOCK_FAILED",
@@ -135,13 +133,10 @@ final class SAEScreenLockViewController: ScreenLockViewController {
     private func cancelShareExperience() {
         invokeCompletion(didUnlock: false)
     }
-}
 
-extension SAEScreenLockViewController: ScreenLockViewDelegate {
+    // MARK: - ScreenLockViewDelegate:
 
     func unlockButtonWasTapped() {
-        AssertIsOnMainThread()
-
         Logger.info("unlockButtonWasTapped")
 
         tryToPresentAuthUIToUnlockScreenLock()
diff --git a/SignalUI/ViewControllers/ScreenLockViewController.swift b/SignalUI/ViewControllers/ScreenLockViewController.swift
index 0c0adddcdf..e5675f454a 100644
--- a/SignalUI/ViewControllers/ScreenLockViewController.swift
+++ b/SignalUI/ViewControllers/ScreenLockViewController.swift
@@ -6,6 +6,7 @@
 import SignalServiceKit
 import UIKit
 
+@MainActor
 public protocol ScreenLockViewDelegate: AnyObject {
     func unlockButtonWasTapped()
 }
@@ -35,20 +36,18 @@ open class ScreenLockViewController: UIViewController {
 
     private lazy var imageViewLogo = UIImageView(image: UIImage(named: "signal-logo-128-launch-screen"))
     private static var buttonHeight: CGFloat { 40 }
-    private lazy var buttonUnlockUI = OWSFlatButton.button(
-        title: OWSLocalizedString(
+    private lazy var buttonUnlockUI = UIButton(
+        configuration: .largePrimary(title: OWSLocalizedString(
             "SCREEN_LOCK_UNLOCK_SIGNAL",
             comment: "Label for button on lock screen that lets users unlock Signal.",
-        ),
-        font: OWSFlatButton.fontForHeight(ScreenLockViewController.buttonHeight),
-        titleColor: UIColor.Signal.label,
-        backgroundColor: UIColor.Signal.tertiaryFill,
-        target: self,
-        selector: #selector(unlockUIButtonTapped),
+        )),
+        primaryAction: UIAction { [weak self] _ in
+            self?.unlockUIButtonTapped()
+        },
     )
 
-    override open func loadView() {
-        super.loadView()
+    override open func viewDidLoad() {
+        super.viewDidLoad()
 
         view.backgroundColor = UIColor.Signal.background
 
@@ -57,8 +56,9 @@ open class ScreenLockViewController: UIViewController {
         imageViewLogo.autoVCenterInSuperview()
         imageViewLogo.autoSetDimensions(to: .square(128))
 
+        buttonUnlockUI.configuration?.baseForegroundColor = .Signal.label
+        buttonUnlockUI.configuration?.baseBackgroundColor = .Signal.tertiaryFill
         view.addSubview(buttonUnlockUI)
-        buttonUnlockUI.autoSetDimension(.height, toSize: ScreenLockViewController.buttonHeight)
         buttonUnlockUI.autoPinWidthToSuperview(withMargin: 50)
         buttonUnlockUI.autoPinBottomToSuperviewMargin(withInset: 65)
 
@@ -89,8 +89,35 @@ open class ScreenLockViewController: UIViewController {
         UIDevice.current.defaultSupportedOrientations
     }
 
-    @objc
-    private func unlockUIButtonTapped(_ sender: Any) {
+    private func unlockUIButtonTapped() {
         delegate?.unlockButtonWasTapped()
     }
 }
+
+#if DEBUG
+
+@available(iOS 17, *)
+#Preview("State: none") {
+    let vc = ScreenLockViewController()
+    vc.view.isHidden = false // force view to load
+    vc.updateUIWithState(.none)
+    return vc
+}
+
+@available(iOS 17, *)
+#Preview("State: screenProtection") {
+    let vc = ScreenLockViewController()
+    vc.view.isHidden = false // force view to load
+    vc.updateUIWithState(.screenLock)
+    return vc
+}
+
+@available(iOS 17, *)
+#Preview("State: screenLock") {
+    let vc = ScreenLockViewController()
+    vc.view.isHidden = false // force view to load
+    vc.updateUIWithState(.screenProtection)
+    return vc
+}
+
+#endif