Rider 2024.1.2 does not appear to properly support .slnx solution files

Hi JetBrains Support,

I am using JetBrains Rider 2024.1.2 and I believe Rider may not fully support .slnx solution files yet, or there may be a bug with how the project explorer handles them.

Environment:

JetBrains Rider 2024.1.2
Build #RD-241.15989.179
Built on May 6, 2024
Runtime version: 17.0.10+1-b1207.14 aarch64
VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o.
macOS 26.5.1
.NET Core v8.0.1 ARM64

Issue:

When opening my repository in Rider, I can see hidden folders such as .git and .idea in the File System view, so hidden folders are not the issue.

However, the solution/project structure does not appear to behave correctly when using a .slnx file. The file system contents are visible, but Rider does not seem to treat the .slnx solution the same way it would treat a traditional .sln file.

What I observed:

1. Hidden folders are visible in File System view.
2. The repository structure is visible on disk.
3. The project appears to be opened through the file system rather than properly recognized as a solution.
4. Rider does not seem to expose the expected solution/project behavior for the .slnx file.

Expected behavior:

Rider should recognize and fully support .slnx files the same way Visual Studio and the .NET tooling are beginning to support them, or Rider should clearly indicate that .slnx files are not currently supported.

Actual behavior:

The repository opens, but Rider does not appear to properly load or manage the .slnx solution structure.

Can you confirm whether .slnx files are supported in Rider 2024.1.2, and if not, whether support is planned for a future release?

Thank you.