On Linkedin, videos are limited in weight, duration and format.
Minimum file size: 75KB
Maximum file size: 5GB
Minimum duration: 3 seconds
Maximum length: 10 minutes (except for "sponsored" videos in advertisements, which can be up to 30 minutes)
There are also restrictions on the orientation, aspect ratio and type of the video :
Orientation: horizontal or vertical.
Aspect ratio: 1:2.4 or 2.4:1
Resolution interval: 256×144 to 4096×2304
Frames per second (fps/fps): 10 - 60 frames per second
Bit rates (synthesis of the information sent per second): 192 kbps - 30 Mbps
Supported file formats: ASF, AVI, FLV, MPEG-1, MPEG-4, MKV, QuickTime, WebM, H264/AVC, MP4, VP8, VP9, WMV2, and WMV3.
Enabling the auto-play option depends on whether you published the video directly (natively) on Linkedin or whether you shared a link to a platform external to Linkedin (such as Youtube):
If the video is "native" from Linkedin's point of view, auto-play works
If the video is stored outside Linkedin, auto-play does not work.