Steps to reproduce the issue

After upgrade to Joomla 3.7.3 the layout switcher uses only tablet layout. If i delete layout-tablet.css it uses only layout-mobile.css. And again i delete mobile layout it uses the standart layout.css. Alone all layouts work fine. In 3.7.2 it works as intended. After 3.7.3 to 3.8.1 can't choose proper layout.

System information (as much as possible)

Template is JA University.
Linux web 3.16.0-4-686-pae #1 SMP Debian 3.16.7
Database version 5.5.49-0+deb8u1
Php 5.6.23-0+deb8u1
Apache