Regex: options not being processed?

It seems the regex options in the option(boolean) form are not being processed:

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1 ?- re_matchsub("\\d.*\\d"/s,"1\n2",Dict,[]).
Dict = re_match{0:"1\n2"}.

2 ?- re_matchsub("\\d.*\\d","1\n2",Dict,[dotall(true)]).

It works fine with the /s at the end of the regex, but dotall(true) is not being processed.

There are two types of options to the regex predicates: those that affect the pattern and are passed to the regex compilation and those that affect the execution. As these predicates cache and reuse the compiled patterns flags that apply to the compilation have no effect.

I’ve added a couple of lines to the docs.

Thanks! Appreciate the clarification, especially adding it to the docs.