The suffix "-8m4v" appears to be a truncated or modified version of a standard video container.
This specific naming pattern is characteristic of Samsung Galaxy or other Android smartphones . Unlike iPhones (which typically use "IMG_xxxx"), these devices generate filenames based on the exact second the recording started. Vid 20181003 131635-8m4v
Try changing the .8m4v suffix to a standard .mp4 or .m4v . The suffix "-8m4v" appears to be a truncated
Uploads to Google Photos or OneDrive where the original metadata is preserved in the title. similar to MP4.
A common video container format developed by Apple, similar to MP4.