We generate those tokens with a prefix, so that we
can decide by looking at a token, whether it's an API Token
or a different kind of token, so that we can decide which
code path to choose for validating the token.
The usage of access tokens as Bearer token has the usability advantage,
that you can paste them as plaintext into tools that expect you
to specify the token as a header.
Also the Basic auth approach for our old tokens usually rather caused
issues, such as browsers prompting for credentials in surprising situations.
If we were to deprecate basic authentication one day, this change today could've
been the first step towards that.
Dombi Attila