Hi,
Thank you for the details.
I just tested with multiple devices (Chrome and Safari browsers), but it seems to be okay on our ends. I search for something (select Land), then click on a result, then click back – and I am taken back to the previous page: https://www.youtube.com/watch?v=3IBeWkKmaGU
This may differ on older devices, or different browsers, but webkit based should be okay. Some devices may have the local cache, or the pushstates control disabled, that could explain the issue – unfortuantely with those there is nothing to do, ultimately the browser decides if it keeps the pushstate cache or not.