Bug#1122456: properties-cpp: FTBFS: error: Style sheet '/<>/doc/extra.css' specified by HTML_EXTRA_STYLESHEET does not exist!

[Jeremy Bícha]

Santiago, I am unable to verify this build failure locally or on Salsa
CI today. Are you still experiencing this issue?

https://salsa.debian.org/ubports-team/properties-cpp/-/pipelines/1040441

Thank you,
Jeremy Bícha