as stated at the end of the post, the parameters are ignored and it seems things did not evolve since:
The comment that states custom parameters are ignored was from May 13. Support for custom parameters was subsequently added on May 20.
Note that the comment is referring to custom parameters which is why we explicitly ignore reserved keywords (token, commit, branch) which we read and use in other parts of the code.
I have tested this feature and can confirm it works, although it may not work for some providers due to limitations with their API (I am specifically thinking of Gogs).