MR adding the flag and build-dep:
https://salsa.debian.org/debian/strongswan/-/merge_requests/11
libstrongswan-extra-plugins debdiff:
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File lists identical (after any substitutions)
Control files: lines which differ (wdiff format)
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Depends: libstrongswan (= 5.9.1-1), libc6 (>= 2.25), libcurl4 (>=
7.16.2), libgcrypt20 (>= [-1.8.0),-] {+1.9.0),+} libgpg-error0 (>=
1.14), libldap-2.4-2 (>= [-2.4.7)-] {+2.4.7), libtss2-sys1 (>= 3.0.1)+}
Installed-Size: [-732-] {+752+}
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Note the new libtss2-sys1 dependency.
Paride