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UTM 9.3-11 build, for some reason, I have now had to uncheck the ' Do not proxy HTTPS traffic in Transparent Mode' box in Web Protection >Web Filtering > HTTPS tab.
I haven't made any changes to anything on ISP or LAN side, and by chance of just simple deduction of going through settings and disabling/re-enabling, I had figured this one out - but I don't know why this is an issue all of a sudden.
ANY HTTPS traffic (games, websites, etc.) that require an HTTPS connection will NOT load at all until I had unchecked that box.
Web caching was not enabled, and I now currently have it enabled.
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