Adding Query Strings Based on Filters

Hello, I found this code here: https://gist.github.com/dcooney/87731ec3ec553f5a10bfe5cadab47948 and this is already working on my site, but I would like to add the functionality to pass a query string on the address bar for the filters. Is this possible to do?

Example:

http://www.example.com/?category=test&tag=test2

Thanks!

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