Absolute time indication

I want to change the time display in “Activity” and “Files list on File” from relative time display to absolute time display.
Please tell me how to change it.

Nextcloud version (eg, 10.0.2): 12.0.0
Operating system and version (eg, Ubuntu 16.04): CentOS 7.3
Apache or nginx version (eg, Apache 2.4.25): nginx 1.11.10
PHP version (eg, 5.6): PHP 7.1.7