Unfortunately, it seems that it stopped working a couple of days ago. It looks like SharpTools may have deprecated the use of JavaScript in hyperlinks.
Thanks for posting and sorry to hear that the special GET syntax with the proxy option isn’t working as expected. I’m taking a look and will let you know what I find.
Some of the changes from the Smarter Kiosk Mode + New Navigate Back Feature release appears to have caused this regression, so I made some improvements to better support ALL of the cases.
Make sure to refresh your browser while viewing SharpTools to pull in the latest updates.