Issues when creating .sln and .slnx using command

[ArabellaQi]

Describe the Issue

For .sln: When creating a .sln file using the command, a .slnx file is created.

For .slnx: When attempting to create a .slnx file using the command, no templates or subcommands found matching: ‘slnx’.

Steps To Reproduce

1.Create a C# Console App then the less-solution will be opened.
2.Run dotnet new sln --name ConsoleApp1 and dotnet new slnx --name ConsoleApp1 in the terminal and observe.

Expected Behavior

1.When using the command to create an SLN, a .sln file will be generated.
2.When using the command to create an SLNX, a .slnx file will be generated.

Environment Information

.NET Install Tool: Pre-release 3.0.0
C# Dev Kit Extension: Pre-release 1.92.4
C# Extension: Pre-release 2.112.45
.NET SDKs:  10.0.102
VSCode Insider: 1.109.0
Platform: Windows X64 

[ArabellaQi]

May I know if there is a new setting that default to generating .slnx file? When I open an empty folder and create a solution with the .sln format using .NET: New Project in the command palette, the generated solution file is .slnx, preventing CSDK from activating.

[Michael-Eng]

This is likely due to the fact that dotnet.exe new sln now defaults to slnx