This refers to Upfiles.com , a popular file-hosting service. It’s a "no-frills" platform where users upload large files to share via direct links.
This usually refers to a collection of files. In the gaming world, these could be "texture packs" or "mod packs." In general data circles, it refers to a compressed bundle of related assets. packs cp upfiles txt link
File hosts like Upfiles frequently delete content due to inactivity or copyright strikes. If you are searching for a specific "txt link" from a forum post made six months ago, there is a 90% chance the link is already broken. This refers to Upfiles