Build fails with "Instance of MicHeaderBlock did not understand #counter"
When changing something, the build fails
/_pillar/build/pillar build html -a
775Instance of MicHeaderBlock did not understand #counter
776MicHeaderBlock(Object)>>doesNotUnderstand: #counter
777PRHTMLWriter(PRDocumentWriter)>>writeCounterForHeader:
see https://gitlab.inria.fr/RMOD/website/-/jobs/2325158#L773