In attempt to reproduce issue #557 I've created this flutter demo pro…

…ject from scratch. Still wasn't able to reproduce. Leaving it here for reference.

demo/.flutter-plugins

@@ -0,0 +1,6 @@
+# This is a generated file; do not edit or check into version control.
+ably_flutter=/Users/admin/.pub-cache/hosted/pub.dev/ably_flutter-1.2.36/
+firebase_core=/Users/admin/.pub-cache/hosted/pub.dev/firebase_core-3.11.0/
+firebase_core_web=/Users/admin/.pub-cache/hosted/pub.dev/firebase_core_web-2.20.0/
+firebase_messaging=/Users/admin/.pub-cache/hosted/pub.dev/firebase_messaging-15.2.2/
+firebase_messaging_web=/Users/admin/.pub-cache/hosted/pub.dev/firebase_messaging_web-3.10.2/

demo/.flutter-plugins-dependencies

@@ -0,0 +1 @@
+{"info":"This is a generated file; do not edit or check into version control.","plugins":{"ios":[{"name":"ably_flutter","path":"/Users/admin/.pub-cache/hosted/pub.dev/ably_flutter-1.2.36/","native_build":true,"dependencies":[]},{"name":"firebase_core","path":"/Users/admin/.pub-cache/hosted/pub.dev/firebase_core-3.11.0/","native_build":true,"dependencies":[]},{"name":"firebase_messaging","path":"/Users/admin/.pub-cache/hosted/pub.dev/firebase_messaging-15.2.2/","native_build":true,"dependencies":["firebase_core"]}],"android":[{"name":"ably_flutter","path":"/Users/admin/.pub-cache/hosted/pub.dev/ably_flutter-1.2.36/","native_build":true,"dependencies":[]},{"name":"firebase_core","path":"/Users/admin/.pub-cache/hosted/pub.dev/firebase_core-3.11.0/","native_build":true,"dependencies":[]},{"name":"firebase_messaging","path":"/Users/admin/.pub-cache/hosted/pub.dev/firebase_messaging-15.2.2/","native_build":true,"dependencies":["firebase_core"]}],"macos":[{"name":"firebase_core","path":"/Users/admin/.pub-cache/hosted/pub.dev/firebase_core-3.11.0/","native_build":true,"dependencies":[]},{"name":"firebase_messaging","path":"/Users/admin/.pub-cache/hosted/pub.dev/firebase_messaging-15.2.2/","native_build":true,"dependencies":["firebase_core"]}],"linux":[],"windows":[{"name":"firebase_core","path":"/Users/admin/.pub-cache/hosted/pub.dev/firebase_core-3.11.0/","native_build":true,"dependencies":[]}],"web":[{"name":"firebase_core_web","path":"/Users/admin/.pub-cache/hosted/pub.dev/firebase_core_web-2.20.0/","dependencies":[]},{"name":"firebase_messaging_web","path":"/Users/admin/.pub-cache/hosted/pub.dev/firebase_messaging_web-3.10.2/","dependencies":["firebase_core_web"]}]},"dependencyGraph":[{"name":"ably_flutter","dependencies":[]},{"name":"firebase_core","dependencies":["firebase_core_web"]},{"name":"firebase_core_web","dependencies":[]},{"name":"firebase_messaging","dependencies":["firebase_core","firebase_messaging_web"]},{"name":"firebase_messaging_web","dependencies":["firebase_core","firebase_core_web"]}],"date_created":"2025-02-09 13:58:31.133761","version":"3.27.2","swift_package_manager_enabled":false}

demo/.metadata

@@ -0,0 +1,45 @@
+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled and should not be manually edited.
+
+version:
+  revision: "68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3"
+  channel: "stable"
+
+project_type: app
+
+# Tracks metadata for the flutter migrate command
+migration:
+  platforms:
+    - platform: root
+      create_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+      base_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+    - platform: android
+      create_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+      base_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+    - platform: ios
+      create_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+      base_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+    - platform: linux
+      create_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+      base_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+    - platform: macos
+      create_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+      base_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+    - platform: web
+      create_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+      base_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+    - platform: windows
+      create_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+      base_revision: 68415ad1d920f6fe5ec284f5c2febf7c4dd5b0b3
+
+  # User provided section
+
+  # List of Local paths (relative to this file) that should be
+  # ignored by the migrate tool.
+  #
+  # Files that are not part of the templates will be ignored by default.
+  unmanaged_files:
+    - 'lib/main.dart'
+    - 'ios/Runner.xcodeproj/project.pbxproj'

demo/.tool-versions

@@ -0,0 +1 @@
+ruby 3.3.6

demo/README.md

@@ -0,0 +1,16 @@
+# flutter_demo
+
+A new Flutter project.
+
+## Getting Started
+
+This project is a starting point for a Flutter application.
+
+A few resources to get you started if this is your first Flutter project:
+
+- [Lab: Write your first Flutter app](https://docs.flutter.dev/get-started/codelab)
+- [Cookbook: Useful Flutter samples](https://docs.flutter.dev/cookbook)
+
+For help getting started with Flutter development, view the
+[online documentation](https://docs.flutter.dev/), which offers tutorials,
+samples, guidance on mobile development, and a full API reference.

demo/analysis_options.yaml

@@ -0,0 +1,28 @@
+# This file configures the analyzer, which statically analyzes Dart code to
+# check for errors, warnings, and lints.
+#
+# The issues identified by the analyzer are surfaced in the UI of Dart-enabled
+# IDEs (https://dart.dev/tools#ides-and-editors). The analyzer can also be
+# invoked from the command line by running `flutter analyze`.
+
+# The following line activates a set of recommended lints for Flutter apps,
+# packages, and plugins designed to encourage good coding practices.
+include: package:flutter_lints/flutter.yaml
+
+linter:
+  # The lint rules applied to this project can be customized in the
+  # section below to disable rules from the `package:flutter_lints/flutter.yaml`
+  # included above or to enable additional rules. A list of all available lints
+  # and their documentation is published at https://dart.dev/lints.
+  #
+  # Instead of disabling a lint rule for the entire project in the
+  # section below, it can also be suppressed for a single line of code
+  # or a specific dart file by using the `// ignore: name_of_lint` and
+  # `// ignore_for_file: name_of_lint` syntax on the line or in the file
+  # producing the lint.
+  rules:
+    # avoid_print: false  # Uncomment to disable the `avoid_print` rule
+    # prefer_single_quotes: true  # Uncomment to enable the `prefer_single_quotes` rule
+
+# Additional information about this file can be found at
+# https://dart.dev/guides/language/analysis-options

demo/firebase.json

@@ -0,0 +1 @@
+{"flutter":{"platforms":{"ios":{"default":{"projectId":"fcmappletest-c7f74","appId":"1:180953712967:ios:ee01c9201e44622d9d2462","uploadDebugSymbols":false,"fileOutput":"ios/Runner/GoogleService-Info.plist"}},"dart":{"lib/firebase_options.dart":{"projectId":"fcmappletest-c7f74","configurations":{"ios":"1:180953712967:ios:ee01c9201e44622d9d2462"}}}}}}

demo/ios/.gitignore

@@ -0,0 +1,34 @@
+**/dgph
+*.mode1v3
+*.mode2v3
+*.moved-aside
+*.pbxuser
+*.perspectivev3
+**/*sync/
+.sconsign.dblite
+.tags*
+**/.vagrant/
+**/DerivedData/
+Icon?
+**/Pods/
+**/.symlinks/
+profile
+xcuserdata
+**/.generated/
+Flutter/App.framework
+Flutter/Flutter.framework
+Flutter/Flutter.podspec
+Flutter/Generated.xcconfig
+Flutter/ephemeral/
+Flutter/app.flx
+Flutter/app.zip
+Flutter/flutter_assets/
+Flutter/flutter_export_environment.sh
+ServiceDefinitions.json
+Runner/GeneratedPluginRegistrant.*
+
+# Exceptions to above rules.
+!default.mode1v3
+!default.mode2v3
+!default.pbxuser
+!default.perspectivev3

demo/ios/Flutter/AppFrameworkInfo.plist

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+  <key>CFBundleDevelopmentRegion</key>
+  <string>en</string>
+  <key>CFBundleExecutable</key>
+  <string>App</string>
+  <key>CFBundleIdentifier</key>
+  <string>io.flutter.flutter.app</string>
+  <key>CFBundleInfoDictionaryVersion</key>
+  <string>6.0</string>
+  <key>CFBundleName</key>
+  <string>App</string>
+  <key>CFBundlePackageType</key>
+  <string>FMWK</string>
+  <key>CFBundleShortVersionString</key>
+  <string>1.0</string>
+  <key>CFBundleSignature</key>
+  <string>????</string>
+  <key>CFBundleVersion</key>
+  <string>1.0</string>
+  <key>MinimumOSVersion</key>
+  <string>12.0</string>
+</dict>
+</plist>

demo/ios/Flutter/Debug.xcconfig

@@ -0,0 +1,2 @@
+#include? "Pods/Target Support Files/Pods-Runner/Pods-Runner.debug.xcconfig"
+#include "Generated.xcconfig"

demo/ios/Flutter/Release.xcconfig

@@ -0,0 +1,2 @@
+#include? "Pods/Target Support Files/Pods-Runner/Pods-Runner.release.xcconfig"
+#include "Generated.xcconfig"

demo/ios/Podfile

@@ -0,0 +1,51 @@
+# Uncomment this line to define a global platform for your project
+platform :ios, '13.0'
+
+# CocoaPods analytics sends network stats synchronously affecting flutter build latency.
+ENV['COCOAPODS_DISABLE_STATS'] = 'true'
+
+project 'Runner', {
+  'Debug' => :debug,
+  'Profile' => :release,
+  'Release' => :release,
+}
+
+def flutter_root
+  generated_xcode_build_settings_path = File.expand_path(File.join('..', 'Flutter', 'Generated.xcconfig'), __FILE__)
+  unless File.exist?(generated_xcode_build_settings_path)
+    raise "#{generated_xcode_build_settings_path} must exist. If you're running pod install manually, make sure flutter pub get is executed first"
+  end
+
+  File.foreach(generated_xcode_build_settings_path) do |line|
+    matches = line.match(/FLUTTER_ROOT\=(.*)/)
+    return matches[1].strip if matches
+  end
+  raise "FLUTTER_ROOT not found in #{generated_xcode_build_settings_path}. Try deleting Generated.xcconfig, then run flutter pub get"
+end
+
+require File.expand_path(File.join('packages', 'flutter_tools', 'bin', 'podhelper'), flutter_root)
+
+flutter_ios_podfile_setup
+
+target 'Runner' do
+  use_frameworks!
+  use_modular_headers!
+
+  flutter_install_all_ios_pods File.dirname(File.realpath(__FILE__))
+  target 'RunnerTests' do
+    inherit! :search_paths
+  end
+end
+
+post_install do |installer|
+  installer.pods_project.targets.each do |target|
+    flutter_additional_ios_build_settings(target)
+  end
+  installer.generated_projects.each do |project|
+    project.targets.each do |target|
+      target.build_configurations.each do |config|
+        config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '13.0'
+      end
+    end
+  end
+end

demo/ios/Podfile.lock

@@ -0,0 +1,128 @@
+PODS:
+  - Ably (1.2.33):
+    - AblyDeltaCodec (= 1.3.3)
+    - msgpack (= 0.4.0)
+  - ably_flutter (1.2.36):
+    - Ably (= 1.2.33)
+    - Flutter
+  - AblyDeltaCodec (1.3.3)
+  - Firebase/CoreOnly (11.7.0):
+    - FirebaseCore (~> 11.7.0)
+  - Firebase/Messaging (11.7.0):
+    - Firebase/CoreOnly
+    - FirebaseMessaging (~> 11.7.0)
+  - firebase_core (3.11.0):
+    - Firebase/CoreOnly (= 11.7.0)
+    - Flutter
+  - firebase_messaging (15.2.2):
+    - Firebase/Messaging (= 11.7.0)
+    - firebase_core
+    - Flutter
+  - FirebaseCore (11.7.0):
+    - FirebaseCoreInternal (~> 11.7.0)
+    - GoogleUtilities/Environment (~> 8.0)
+    - GoogleUtilities/Logger (~> 8.0)
+  - FirebaseCoreInternal (11.7.0):
+    - "GoogleUtilities/NSData+zlib (~> 8.0)"
+  - FirebaseInstallations (11.7.0):
+    - FirebaseCore (~> 11.7.0)
+    - GoogleUtilities/Environment (~> 8.0)
+    - GoogleUtilities/UserDefaults (~> 8.0)
+    - PromisesObjC (~> 2.4)
+  - FirebaseMessaging (11.7.0):
+    - FirebaseCore (~> 11.7.0)
+    - FirebaseInstallations (~> 11.0)
+    - GoogleDataTransport (~> 10.0)
+    - GoogleUtilities/AppDelegateSwizzler (~> 8.0)
+    - GoogleUtilities/Environment (~> 8.0)
+    - GoogleUtilities/Reachability (~> 8.0)
+    - GoogleUtilities/UserDefaults (~> 8.0)
+    - nanopb (~> 3.30910.0)
+  - Flutter (1.0.0)
+  - GoogleDataTransport (10.1.0):
+    - nanopb (~> 3.30910.0)
+    - PromisesObjC (~> 2.4)
+  - GoogleUtilities/AppDelegateSwizzler (8.0.2):
+    - GoogleUtilities/Environment
+    - GoogleUtilities/Logger
+    - GoogleUtilities/Network
+    - GoogleUtilities/Privacy
+  - GoogleUtilities/Environment (8.0.2):
+    - GoogleUtilities/Privacy
+  - GoogleUtilities/Logger (8.0.2):
+    - GoogleUtilities/Environment
+    - GoogleUtilities/Privacy
+  - GoogleUtilities/Network (8.0.2):
+    - GoogleUtilities/Logger
+    - "GoogleUtilities/NSData+zlib"
+    - GoogleUtilities/Privacy
+    - GoogleUtilities/Reachability
+  - "GoogleUtilities/NSData+zlib (8.0.2)":
+    - GoogleUtilities/Privacy
+  - GoogleUtilities/Privacy (8.0.2)
+  - GoogleUtilities/Reachability (8.0.2):
+    - GoogleUtilities/Logger
+    - GoogleUtilities/Privacy
+  - GoogleUtilities/UserDefaults (8.0.2):
+    - GoogleUtilities/Logger
+    - GoogleUtilities/Privacy
+  - msgpack (0.4.0)
+  - nanopb (3.30910.0):
+    - nanopb/decode (= 3.30910.0)
+    - nanopb/encode (= 3.30910.0)
+  - nanopb/decode (3.30910.0)
+  - nanopb/encode (3.30910.0)
+  - PromisesObjC (2.4.0)
+
+DEPENDENCIES:
+  - ably_flutter (from `.symlinks/plugins/ably_flutter/ios`)
+  - firebase_core (from `.symlinks/plugins/firebase_core/ios`)
+  - firebase_messaging (from `.symlinks/plugins/firebase_messaging/ios`)
+  - Flutter (from `Flutter`)
+
+SPEC REPOS:
+  trunk:
+    - Ably
+    - AblyDeltaCodec
+    - Firebase
+    - FirebaseCore
+    - FirebaseCoreInternal
+    - FirebaseInstallations
+    - FirebaseMessaging
+    - GoogleDataTransport
+    - GoogleUtilities
+    - msgpack
+    - nanopb
+    - PromisesObjC
+
+EXTERNAL SOURCES:
+  ably_flutter:
+    :path: ".symlinks/plugins/ably_flutter/ios"
+  firebase_core:
+    :path: ".symlinks/plugins/firebase_core/ios"
+  firebase_messaging:
+    :path: ".symlinks/plugins/firebase_messaging/ios"
+  Flutter:
+    :path: Flutter
+
+SPEC CHECKSUMS:
+  Ably: 1d78e5dec56db6d2cf91b10d14fea796ce591bae
+  ably_flutter: b4e0bffd35488a8c29d2ac7f35c00f80defab856
+  AblyDeltaCodec: add5d06a756b3581b12aab5b5500a320b8c55bea
+  Firebase: a64bf6a8546e6eab54f1c715cd6151f39d2329f4
+  firebase_core: aa979ae726f00b3ef4ccf59dfb96170af84efbd4
+  firebase_messaging: 3af84b6a90aeac4d7a67fbf4c43a91e7083bea1f
+  FirebaseCore: 3227e35f4197a924206fbcdc0349325baf4f5de4
+  FirebaseCoreInternal: d6c17dafc8dc33614733a8b52df78fcb4394c881
+  FirebaseInstallations: 9347e719c3d52d8d7b9074b2c32407dd027305e9
+  FirebaseMessaging: 00ece041b71ddb52a2862ffdee73fb6e9824bd0c
+  Flutter: e0871f40cf51350855a761d2e70bf5af5b9b5de7
+  GoogleDataTransport: aae35b7ea0c09004c3797d53c8c41f66f219d6a7
+  GoogleUtilities: 26a3abef001b6533cf678d3eb38fd3f614b7872d
+  msgpack: c85f6251873059738472ae136951cec5f30f3251
+  nanopb: fad817b59e0457d11a5dfbde799381cd727c1275
+  PromisesObjC: f5707f49cb48b9636751c5b2e7d227e43fba9f47
+
+PODFILE CHECKSUM: ce1e501d1d2e92c4c56b5def86bac658492ab7a9
+
+COCOAPODS: 1.16.2