If you are looking for a "good blog post" on this topic, it is usually found in discussions about to make high-quality video files compatible with social media or mobile devices. Why you see "mkv.mp4"
This typically happens when a user re-saves an MKV file (a high-quality "container" that holds multiple audio/subtitle tracks) as an MP4 (a more widely compatible format) without removing the original extension. Key Resources for Video Conversion 9700.mkv.mp4
Adobe's Guide to MKV explains why people use MKV for archiving and MP4 for sharing. If you are looking for a "good blog
FastPix has a detailed 2026 comparison on when to use each container for streaming versus storage. FastPix has a detailed 2026 comparison on when
Are you trying to with a file named 9700, or MKV vs MP4: Choosing the Right Streaming Format in 2026
If you are an OBS user, the OBS Project Forum has extensive posts on "remuxing" recordings so they don't break if your computer crashes.