You can use Infinity version 6.3.1 as a third-party client for Reddit without logging in.

I don't know if there are other ways to use Reddit without using its own client, but I wanted to inform you.

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Can confirm this, but has some bugs like not playing some videos

I haven't experienced that personally but Reddit's Imgur has also cracked down on VPNs and many hosted pics and gifs will not load, depending on your selected server.