cxx_std_26 not available with Clang 19

I'd like to do this on a global scale:

add_library(MyBaseLibrary INTERFACE)

target_compile_features(MyBaseLibrary
  INTERFACE
    cxx_std_26
)

But I get an error:

[cmake] CMake Error in app/CMakeLists.txt:
[cmake]   The compiler feature "cxx_std_26" is not known to CXX compiler
[cmake] 
[cmake]   "Clang"
[cmake] 
[cmake]   version 19.0.0.

Is this expected and I misunderstand how to use target compile features?

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