[exim] String to list

I used to be able to use strings where a list was wanted, but that
seem to have stopped working somewhere between 4.80 and 4.84

eg:

in a transport:

remove_headers = ${extract{TH}{$acl_m_xconfig}{$value}}

the expansion might return a list for two or more headers eg:

X-Foo:X-Bar

But the remove operation doesn't accept that now. Is there a new to get that effect?


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umop apisdn