Since the support policy for Standard Term Support (STS) releases was recently changed in September 2025 https://devblogs.microsoft.com/dotnet/dotnet-sts-releases-supported-for-24-months/ the x on May 2026 was previously for .NET 9 when it was supported for 18 months and should be removed. The bar for .NET 9 was extended but the x was still left there, maybe a new symbol should be used or both the circle and the x should be beside each other on November 2026, I'm sure there's some UX experts out there that have a better solution :).
There's also no legend for how to interpret the different symbols but they are instead inferred from context.
