Apple doesn't want multiple videos playing simultaneously on mobile.
Click below to start playback. On mobile, one click will pause the other.
Funnily enough, on Safari Desktop, clicking
video2 works, but
video1 permanently stops
Starting videos muted, then allowing manual play, seems to work quite well and looks really classy on iOS 11. Unfortunately controls are kinda ugly on other platforms.
Update one day later: iPhone reliably freezes and shuts down with 3+ unmuted videos playing. May be a bad interaction between Mithril.js and MediaStreams.