`.cppm` is the widely used extension for C++20 module interface units, supported by MSVC, Clang, and GCC. Currently Zed doesn't recognize it as C++, so users get no syntax highlighting or LSP support. Changes: `crates/languages/src/cpp/config.toml`: add cppm to path_suffixes `crates/theme/src/icon_theme.rs`: add cppm to the C++ icon matcher https://github.com/search?q=path%3A*.cppm&type=code Release Notes: - N/A