.NET MAUI Multi-Project App's WinUI project has incorrect runtime identifiers

[MSLukeWest]

Description

The csproj has:

win10-x86;win10-x64;win10-arm64

Should be:

win-x86;win-x64;win-arm64

Similarly, in the project under Properties\PublishProfiles there's:

• win10-arm64.pubxml
• win10-x64.pubxml
• win10-x86.pubxml

And these all have RuntimeIdentifier properties with "win10-xxx" values.

Steps to Reproduce

1. Create a new ".NET MAUI Multi-Project App" and select .NET 9.0 (8.0 should repro this too)
2. Inspect project

Link to public reproduction project repository

No response

Version with bug

9.0.40 SR4

Is this a regression from previous behavior?

No, this is something new

Last version that worked well

Unknown/Other

Affected platforms

Windows

Affected platform versions

Any

Did you find any workaround?

Manually edit the project after creation

Relevant log output

[Ying-6]

This issue has been verified Visual Studio 17.14 Preview 1(9.0.40 & 9.0.0 & 8.0.100). Can repro this issue on Windows platform. Not sure if it is expected, so treat it as repro.

MauiApp20.zip

[jfversluis]

We did an attempt to change that but seems we're not quite ready yet: #27883

Actually we merged it for .NET 10: #27679

Do we need this for .NET 9 @MartyIX? @mattleibow ?

[MartyIX]

@mattleibow mentioned in #17142 (comment):

Maybe we can set in templates too. Then new apps are ready to handle the migration

and #17142 (comment):

Putting this as a blocker in .NET 9 srevicing, but I fear it is too late. RIP.

Do we need this for .NET 9 @MartyIX? @mattleibow ?

I'm not sure.

[mattleibow]

I think the issue is that there are bugs in the versions of WASDK and WebVIew2 and Win2D used in .NET MAUI 9 that will make things more difficult. Also, these RIDs were copied from the official Windows App SDK template, so we didn't want to change it.

If we change this, then we will have to update all the docs and things to say win-* and that may be more work than it is worth just for the templates.

I suppose we can revisit this again for .NET 9 if we really want this, but because this way has existed since GA, I am not convinced it is worth it for .NET 9.

For .NET 10, it is already done.

Basically, it is a lot of work just to change the templates and then the docs, which may cause confusion for new and old projects based on samples and documentation. Not sure it is worth it.