diff --git a/docs/building-apps/build-properties.md b/docs/building-apps/build-properties.md
index 6aa958278b11..23ffd354f03e 100644
--- a/docs/building-apps/build-properties.md
+++ b/docs/building-apps/build-properties.md
@@ -1299,6 +1299,12 @@ See [TrimMode](/dotnet/core/deploying/trimming/trimming-options) for a bit more
 > to `false` - to disable trimming, set `TrimMode=copy` instead (a build error
 > will be raised if `PublishTrimmed` is set to `false`).
 
+> [!NOTE]
+> Due to [a known issue](https://github.com/dotnet/runtime/issues/108269), setting `PublishTrimmed`
+> to `true` may cause confusing problems, so the build will report an error if this
+> is detected (the solution is to not set `PublishTrimmed` at all).
+
+
 The `TrimMode` property is equivalent to the existing
 [MtouchLink](#mtouchlink) (for iOS, tvOS and Mac Catalyst) and
 [LinkMode](#linkmode) (for macOS) properties, but the valid properties values
diff --git a/dotnet/targets/Xamarin.Shared.Sdk.targets b/dotnet/targets/Xamarin.Shared.Sdk.targets
index b997fbac4bf3..eee240d82f3a 100644
--- a/dotnet/targets/Xamarin.Shared.Sdk.targets
+++ b/dotnet/targets/Xamarin.Shared.Sdk.targets
@@ -291,13 +291,25 @@
 	<!-- PublishTrimmed must be calculated as part of a target because IsMacEnabled on Windows will be set after connecting to the Mac -->
 	<Target Name="_ComputePublishTrimmed">
 		<PropertyGroup>
-			<_MustTrim Condition="'$(_MustTrim)' == '' And '$(RuntimeIdentifier)' != '' And ($(_ProjectType.EndsWith('ExecutableProject')) Or $(_ProjectType.EndsWith('AppExtensionProject'))) And '$(IsMacEnabled)' == 'true'">true</_MustTrim>
-			<PublishTrimmed Condition="'$(PublishTrimmed)' == '' And '$(_MustTrim)' == 'true'">true</PublishTrimmed>
-
 			<_LinkModeProperty Condition="'$(_PlatformName)' == 'macOS'">LinkMode</_LinkModeProperty>
 			<_LinkModeProperty Condition="'$(_PlatformName)' != 'macOS'">MtouchLink</_LinkModeProperty>
+
+			<!-- The trimmer must be enabled, so if it was explicitly disabled, show an error. -->
+			<_PublishTrimmedError Condition="'$(_PublishTrimmedError)' == '' And '$(PublishTrimmed)' != 'true' And '$(PublishTrimmed)' != ''">true</_PublishTrimmedError>
+			<!-- Also disallow explicitly enabling the trimmer, because it causes problems (https://github.com/dotnet/runtime/issues/108269),
+			     except then PublishAot=true, because then the .NET SDK sets PublishTrimmed=true before we get to here, so we can't distinguish
+			     between developers setting it and the .NET SDK setting it  -->
+			<_PublishTrimmedError Condition="'$(_PublishTrimmedError)' == '' And '$(PublishTrimmed)' != '' And '$(PublishAot)' != 'true'">true</_PublishTrimmedError>
 		</PropertyGroup>
-		<Error Condition="'$(_MustTrim)' == 'true' And '$(PublishTrimmed)' != 'true'" Text="$(_PlatformName) projects must build with PublishTrimmed=true. Current value: $(PublishTrimmed). Set '$(_LinkModeProperty)=None' instead to disable trimming for all assemblies." />
+
+		<Error Condition="'$(_PublishTrimmedError)' == 'true'" Text="$(_PlatformName) projects do not support setting 'PublishTrimmed' to any value (current value: $(PublishTrimmed)). Use the '$(_LinkModeProperty)' property to configure trimming behavior instead." />
+
+		<PropertyGroup>
+			<_MustTrim Condition="'$(_MustTrim)' == '' And '$(RuntimeIdentifier)' != '' And ($(_ProjectType.EndsWith('ExecutableProject')) Or $(_ProjectType.EndsWith('AppExtensionProject'))) And '$(IsMacEnabled)' == 'true'">true</_MustTrim>
+			<PublishTrimmed Condition="'$(PublishTrimmed)' == '' And '$(_MustTrim)' == 'true'">true</PublishTrimmed>
+		</PropertyGroup>
+
+		<!-- Show a warning if the trimmer was disabled because there's no connection to a Mac -->
 		<PropertyGroup Condition="'$(PublishTrimmed)' != '' And '$(IsMacEnabled)' != 'true'">
 			<_PreviousPublishTrimmedValue>$(PublishTrimmed)</_PreviousPublishTrimmedValue>
 			<PublishTrimmed />
diff --git a/tests/dotnet/UnitTests/ProjectTest.cs b/tests/dotnet/UnitTests/ProjectTest.cs
index e5ade9ac2e5f..0046d0eaf68d 100644
--- a/tests/dotnet/UnitTests/ProjectTest.cs
+++ b/tests/dotnet/UnitTests/ProjectTest.cs
@@ -457,7 +457,7 @@ public void InvalidRuntimeIdentifiers (ApplePlatform platform, string runtimeIde
 		[TestCase (ApplePlatform.iOS, "iossimulator-x64", false)]
 		[TestCase (ApplePlatform.iOS, "ios-arm64", true)]
 		[TestCase (ApplePlatform.iOS, "ios-arm64", true, null, "Release")]
-		[TestCase (ApplePlatform.iOS, "ios-arm64", true, "PublishTrimmed=true;UseInterpreter=true")]
+		[TestCase (ApplePlatform.iOS, "ios-arm64", true, "UseInterpreter=true")]
 		[TestCase (ApplePlatform.MacCatalyst, "maccatalyst-arm64;maccatalyst-x64", false)]
 		[Category ("WindowsInclusive")]
 		public void IsNotMacBuild (ApplePlatform platform, string runtimeIdentifiers, bool isDeviceBuild, string? extraProperties = null, string configuration = "Debug")
diff --git a/tests/dotnet/UnitTests/PublishTrimmedTest.cs b/tests/dotnet/UnitTests/PublishTrimmedTest.cs
index f7675e066d2f..124c525822ae 100644
--- a/tests/dotnet/UnitTests/PublishTrimmedTest.cs
+++ b/tests/dotnet/UnitTests/PublishTrimmedTest.cs
@@ -2,13 +2,18 @@ namespace Xamarin.Tests {
 	[TestFixture]
 	public class PublishTrimmedTest : TestBaseClass {
 		[Test]
-		[TestCase (ApplePlatform.iOS, "ios-arm64")]
-		[TestCase (ApplePlatform.TVOS, "tvos-arm64")]
-		[TestCase (ApplePlatform.MacCatalyst, "maccatalyst-arm64")]
-		[TestCase (ApplePlatform.MacCatalyst, "maccatalyst-arm64;maccatalyst-x64")]
-		[TestCase (ApplePlatform.MacOSX, "osx-x64")]
-		[TestCase (ApplePlatform.MacOSX, "osx-arm64;osx-x64")]
-		public void DisableLinker (ApplePlatform platform, string runtimeIdentifiers)
+		[TestCase (ApplePlatform.iOS, "ios-arm64", "false")]
+		[TestCase (ApplePlatform.TVOS, "tvos-arm64", "false")]
+		[TestCase (ApplePlatform.MacCatalyst, "maccatalyst-arm64", "false")]
+		[TestCase (ApplePlatform.MacCatalyst, "maccatalyst-arm64;maccatalyst-x64", "false")]
+		[TestCase (ApplePlatform.MacOSX, "osx-x64", "false")]
+		[TestCase (ApplePlatform.MacOSX, "osx-arm64;osx-x64", "false")]
+
+		[TestCase (ApplePlatform.iOS, "ios-arm64", "true")]
+		[TestCase (ApplePlatform.TVOS, "tvos-arm64", "true")]
+		[TestCase (ApplePlatform.MacCatalyst, "maccatalyst-arm64", "true")]
+		[TestCase (ApplePlatform.MacOSX, "osx-arm64;osx-x64", "true")]
+		public void PublishTrimmedNotSupported (ApplePlatform platform, string runtimeIdentifiers, string value)
 		{
 			var project = "MySimpleApp";
 			Configuration.IgnoreIfIgnoredPlatform (platform);
@@ -17,13 +22,12 @@ public void DisableLinker (ApplePlatform platform, string runtimeIdentifiers)
 			var project_path = GetProjectPath (project, platform: platform);
 			Clean (project_path);
 			var properties = GetDefaultProperties (runtimeIdentifiers);
-			properties ["PublishTrimmed"] = "false";
+			properties ["PublishTrimmed"] = value;
 
 			var rv = DotNet.AssertBuildFailure (project_path, properties);
 			var errors = BinLog.GetBuildLogErrors (rv.BinLogPath).ToArray ();
-			Assert.AreEqual (1, errors.Length, "Error count");
 			var linkModeName = platform == ApplePlatform.MacOSX ? "LinkMode" : "MtouchLink";
-			Assert.AreEqual ($"{platform.AsString ()} projects must build with PublishTrimmed=true. Current value: false. Set '{linkModeName}=None' instead to disable trimming for all assemblies.", errors [0].Message, "Error message");
+			AssertErrorMessages (errors, $"{platform.AsString ()} projects do not support setting 'PublishTrimmed' to any value (current value: {value}). Use the '{linkModeName}' property to configure trimming behavior instead.");
 		}
 	}
 }