To understand what a user is looking for when they type this into a search engine, we have to look at each component of the phrase:
" (a chaotic co-op railroad construction game) and an (the file format for Switch digital games), here are a few ways to frame a post depending on your goal: Option 1: For a Community Update/Announcement
However, the specific string 39link39 often appears in search engine results for sites that index downloadable content, but it isn't a standard versioning term or official patch note. Quick Facts on Unrailed! Updates
Below is an overview of the game and its update features from 2021: Unrailed!