Is there a feature in OpenWrt 19.07 to synchronize time automatically in the browser when the router device is turned off or rebooted, without NTP-client and internet network. maybe there is a script that I can use to get time automatically from the browser without opening the thread and set the syn…

This works for me on a router without RTC: https://openwrt.org/docs/guide-user/services/vpn/wireguard/extras#race_conditions