@rhubarbpieguy, that AppImage still can use OpenSSL 1.0 only, probably next one will contain extra variant of QtNetwork that is supposed to be compatible with 1.1.
Check if 1.0 is available for your system, if yes then try installing it, and let me know if that worked.
uhm, perhaps it ended in some directory where Qt is not looking for it, I think that these are the paths used to locate it:
@rhubarbpieguy, it looks for libssl.so and libcrypto.so (including suffixes),
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