[url_launcher] Improved documentation of the `headers` parameter. (#3097)

Added a clear documentation of the fact that the headers parameter at the launch method is not fully supported by all external browsers.
diff --git a/packages/url_launcher/url_launcher/CHANGELOG.md b/packages/url_launcher/url_launcher/CHANGELOG.md
index 8a15a2b..547e17d 100644
--- a/packages/url_launcher/url_launcher/CHANGELOG.md
+++ b/packages/url_launcher/url_launcher/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 5.7.5
+
+* Improved documentation of the `headers` parameter.
+
 ## 5.7.4
 
 * Update android compileSdkVersion to 29.
diff --git a/packages/url_launcher/url_launcher/lib/url_launcher.dart b/packages/url_launcher/url_launcher/lib/url_launcher.dart
index ccc6833..25aa623 100644
--- a/packages/url_launcher/url_launcher/lib/url_launcher.dart
+++ b/packages/url_launcher/url_launcher/lib/url_launcher.dart
@@ -44,6 +44,9 @@
 /// [enableDomStorage] is an Android only setting. If true, WebView enable
 /// DOM storage.
 /// [headers] is an Android only setting that adds headers to the WebView.
+/// When not using a WebView, the header information is passed to the browser,
+/// some Android browsers do not support the [Browser.EXTRA_HEADERS](https://developer.android.com/reference/android/provider/Browser#EXTRA_HEADERS)
+/// intent extra and the header information will be lost.
 /// [webOnlyWindowName] is an Web only setting . _blank opens the new url in new tab ,
 /// _self opens the new url in current tab.
 /// Default behaviour is to open the url in new tab.
diff --git a/packages/url_launcher/url_launcher/pubspec.yaml b/packages/url_launcher/url_launcher/pubspec.yaml
index 49d52ee..56a6f84 100644
--- a/packages/url_launcher/url_launcher/pubspec.yaml
+++ b/packages/url_launcher/url_launcher/pubspec.yaml
@@ -2,7 +2,7 @@
 description: Flutter plugin for launching a URL on Android and iOS. Supports
   web, phone, SMS, and email schemes.
 homepage: https://github.com/flutter/plugins/tree/master/packages/url_launcher/url_launcher
-version: 5.7.4
+version: 5.7.5
 
 flutter:
   plugin: