Worked on improving file type detection in the macvim-dev/macvim repository by addressing a bug affecting Groff/mom macro support. Focused on correcting the misclassification of .mom files, ensuring they are now recognized as groff rather than nroff, which aligns with established mom macro and groff tooling. This update, implemented as patch 9.1.1909, enhances syntax highlighting and macro editing for developers working with mom-based projects. Leveraged Vim scripting and file type detection expertise to deliver a targeted fix that improves editor reliability and workflow accuracy. The work demonstrates attention to detail in text editor development and language-specific configuration.