Has someone the same problem? I've the last version stable rom xiaomi.eu.
Yesterday for the first time shuts down by itself. Today three times happened.
I don't know what is going on.
Now I'll try to change battery.. I think that the problem could be motherboard..
I finally resolved, I hope! I uninstalled Chrome, then from the TWRP I did wipe cache and Dalvik cache and re-installed the app. Now it seems to work well! Let me know if you work out you!