It is one of the most widely supported formats, compatible with nearly all modern devices, browsers, and operating systems without needing extra software.

Based on the acronym used, it likely relates to one of the following niche contexts: Potential Contexts

MP4 files explained: How to open and use - Adobe

This is the most common use of the "FLR" acronym online, referring to a relationship dynamic where the female partner takes a leadership role. "FLRForLife" would suggest a commitment to this lifestyle.