"Error: poppler cannot be built while another version of poppler is active." Why?

[Thomas R. Murphy]

Is there a reason poppler is setup to disallow in-place updating? This
essentially makes port upgrade outdatedrequire manual intervention when
a rev-bump of poppler comes by. The end of the build log indicates that
this is an intentional prebuild check:

:debug:configure Executing proc-pre-org.macports.configure-configure-0
:error:configure poppler cannot be built while another version of
poppler is active.
:error:configure Please forcibly deactivate the existing copy of
poppler, e.g. by running:
:error:configure     sudo port -f deactivate poppler
:error:configure Then try again.
:error:configure Failed to configure poppler: poppler is active
:debug:configure Error code: NONE

-- 
Thomas R. Murphy (thomas.russell.murphy at case.edu, trm70 at case.edu)
GPG Key ID: 959D48BF
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