Google Chrome

Chrome Automatic Tab Discarding

chrome://flags

automatic tab discarding

SEARCH "chrome prevent tabs unloading"

https://productforums.google.com/forum/#!topic/chrome/RFnp8biGP_g

https://superuser.com/questions/1011135/disabling-tab-discarding-in-google-chrome

DNS cache on Chrome

You can clear the internal cache by visiting :

chrome://net-internals/#dns