concurrency.swift

gistfile1.txt

import SafariServices

// TODO: Remove these conformances if Apple ships their own.
extension SFSafariWindow: @retroactive @unchecked Sendable {}
extension SFSafariPage: @retroactive @unchecked Sendable {}

class SafariExtensionHandler: SFSafariExtensionHandler {

  // MARK: Toolbar
  override func validateToolbarItem(in window: SFSafariWindow, validationHandler: @escaping (Bool, String) -> Void) {
    nonisolated(unsafe) let handler = validationHandler
    Task { @MainActor in
      let url = await window.getURL()
      handler(url != nil, "")
    }
  }

  override func toolbarItemClicked(in window: SFSafariWindow) {
    Task { @MainActor in
      guard let url = await window.getURL() else { return }
      Self.handle(url: url)
    }
  }

  // MARK: Context menu
  override func contextMenuItemSelected(withCommand command: String, in page: SFSafariPage, userInfo: [String : Any]? = nil) {
    guard command == "io.xmollv.abyss.safari.contextmenu" else { return }
    if let userInfo,
       let link = userInfo["link"] as? String,
       let url = URL(string: link),
       url.scheme == "http" || url.scheme == "https" {
      Task { @MainActor in
        Self.handle(url: url)
      }
    } else {
      Task { @MainActor in
        guard let properties = await page.properties(), let url = properties.url else { return }
        Self.handle(url: url)
      }
    }
  }

  // MARK: Private helpers
  @MainActor
  private static func handle(url: URL) {
    guard let urlToOpen = URL(string: "later://x-callback-url/add?url=\(url.absoluteString)") else { return }
    NSWorkspace.shared.open(urlToOpen)
  }
}

private extension SFSafariWindow {
  func getURL() async -> URL? {
    guard let activeTab = await activeTab() else { return nil }
    guard let page = await activeTab.activePage() else { return nil }
    guard let properties = await page.properties() else { return nil }
    return properties.url
  }
}

you should be able to remove those to retroactives and instead do:

@preconcurrency import SafariServices

This is only marginally-better, though. Ultimately, the problem is that SFSafariExtensionHandler isn't correctly annotated. So, we'd have to do pretty deep investigations into how it actually works here. Needing to subclass makes it particularly hard. But I would not be surprised to learn that it is actually a MainActor type. And if that's the case, this will become easy to fix later on.