Error: Unable to perform this action

[doubleday]

Describe the bug
In JetBrains Rider 2025.1.3 / MacOS it does not seem to work at all.

I have a skeleton minimal project and when I try to run the Format With XAML Styler action I get

Unable to perform this action, most likely because of errors in the source code.

To Reproduce
Just try the context action to reformat.

Error Log
Thats what Rider spits out when the action fails:

Message = “Value cannot be null.”
ParamName = value
StackTraceString = “
  at System.ArgumentNullException.Throw(String paramName) in Throw.il:line IL_0006 mvid 77FC
     at System.String.StartsWith(String value, StringComparison comparisonType) in StartsWith.il:line IL_0000 mvid 77FC
     at Xavalon.XamlStyler.Extension.Rider.StylerOptionsFactory.FromSettings(IContextBoundSettingsStoreLive settings, ISolution solution, String projectPath, String sourceFilePath) in D:\a\1\s\src\XamlStyler.Extension.Rider\dotnet\Xavalon.XamlStyler.Extension.Rider\StylerOptionsFactory.cs:line 93
     at Xavalon.XamlStyler.Extension.Rider.StylerOptionsFactory.FromSettings(IContextBoundSettingsStoreLive settings, ISolution solution, IProject project, IPsiSourceFileWithLocation psiSourceFileWithLocation) in D:\a\1\s\src\XamlStyler.Extension.Rider\dotnet\Xavalon.XamlStyler.Extension.Rider\StylerOptionsFactory.cs:line 23
     at Xavalon.XamlStyler.Extension.Rider.XamlStylerReformatContextAction.ExecutePsiTransaction(ISolution solution, IProgressIndicator progress) in D:\a\1\s\src\XamlStyler.Extension.Rider\dotnet\Xavalon.XamlStyler.Extension.Rider\XamlStylerReformatContextAction.cs:line 83
     at JetBrains.ReSharper.Feature.Services.BulbActions.Commands.Shim.ExecutePsiTransactionMethodBulbActionCommand.ExecuteInPsiTransaction(ISolution solution, IProgressIndicator progress) in ExecuteInPsiTransaction.il:line IL_000C mvid B5A1
     at JetBrains.ReSharper.Feature.Services.BulbActions.Commands.BulbActionExecutor.RunPsiTransaction() in RunPsiTransaction.il:line IL_004B mvid B5A1
     at JetBrains.ReSharper.Psi.Transactions.PsiTransactions.Execute(String commandName, Action handler) in Execute.il:line IL_001B mvid 339C

[NicoVermeir]

@doubleday I tried to reproduce this bug, but everything seems to work for me on both MacOS and Windows.
Looking at the stacktrace it seems that the error is originating in the System. namespace, which could point to a corrupt installation somewhere on your system.

Just to make sure we're not missing anything, can you tell us what type of project you're creating? MAUI / Uno / Avalonia / ...?

thank you