From 10017714e5e8a7c5faa85b5d3bfb0bdbe77d426e Mon Sep 17 00:00:00 2001
From: Stefan Ceriu <stefan.ceriu@gmail.com>
Date: Mon, 22 Jun 2026 08:29:33 +0300
Subject: [PATCH] Fix libdispatch main-thread trap when logging Sentry crash
 events

Sentry's beforeSend runs on a background queue, but Event.crashLog read
UIDevice.current there, which carries a main-thread dispatch assertion and
trapped libdispatch. Read the device values on the main thread at setup and
pass them into the now-nonisolated crashLog.
---
 ElementX/Sources/Application/AppCoordinator.swift   | 7 +++++--
 ElementX/Sources/Other/Extensions/SentryEvent.swift | 9 +++++----
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/ElementX/Sources/Application/AppCoordinator.swift b/ElementX/Sources/Application/AppCoordinator.swift
index 237fcee5a..48111b030 100644
--- a/ElementX/Sources/Application/AppCoordinator.swift
+++ b/ElementX/Sources/Application/AppCoordinator.swift
@@ -1020,8 +1020,11 @@ class AppCoordinator: AppCoordinatorProtocol, AuthenticationFlowCoordinatorDeleg
         }
         
         // Mirror every crash into our own logs (which ship with rageshakes) before it's sent to Sentry.
-        options.beforeSend = { event in
-            if let crashLog = event.crashLog {
+        // Device values are read here on the main thread; beforeSend runs on a background queue.
+        let deviceModel = UIDevice.current.model
+        let systemVersion = UIDevice.current.systemVersion
+        options.beforeSend = { @Sendable event in
+            if let crashLog = event.crashLog(deviceModel: deviceModel, systemVersion: systemVersion) {
                 MXLog.error("Sentry crash event \(event.eventId.sentryIdString):\n\(crashLog)")
             }
             return event
diff --git a/ElementX/Sources/Other/Extensions/SentryEvent.swift b/ElementX/Sources/Other/Extensions/SentryEvent.swift
index b15d10cfe..093c85530 100644
--- a/ElementX/Sources/Other/Extensions/SentryEvent.swift
+++ b/ElementX/Sources/Other/Extensions/SentryEvent.swift
@@ -8,12 +8,14 @@
 
 import MatrixRustSDK
 import Sentry
-import UIKit
 
 extension Event {
     /// A human readable crash log matching the format used by the legacy app.
     /// `nil` for non-crash events (handled errors, transactions, etc.).
-    var crashLog: String? {
+    ///
+    /// Device values must be read on the main thread and passed in. `beforeSend`
+    /// runs on a background queue and touching `UIDevice.current` there traps libdispatch.
+    nonisolated func crashLog(deviceModel: String, systemVersion: String) -> String? {
         guard let exceptions,
               exceptions.contains(where: { $0.mechanism?.handled?.boolValue == false }) else {
             return nil
@@ -21,14 +23,13 @@ extension Event {
         
         let reason = exceptions.map { "\($0.type ?? "Unknown"): \($0.value ?? "")" }.joined(separator: "\n")
         let infoPlist = InfoPlistReader.main
-        let device = UIDevice.current
         
         return """
         \(reason)
         Application: \(infoPlist.bundleExecutable) (\(infoPlist.bundleIdentifier))
         Application version: \(infoPlist.bundleShortVersionString) (\(infoPlist.bundleVersion))
         Matrix SDK version: \(sdkGitSha())
-        \(device.model) \(device.systemVersion)
+        \(deviceModel) \(systemVersion)
         """
     }
 }