I've made the recommended change. We were still seeing intermittent, unrelated failures after doing so, and thus I removed the test back in July. I can no longer reproduce these failures, so I've just uploaded 2.3.13+dfsg.1-2 with the offending test enabled anew. Let's see how it goes.
The upstream Notcurses bug is https://github.com/dankamongmen/notcurses/issues/1784. Ubuntu current has 2.3.13+dfsg.1-1, so things have been progressing there naturally for the duration of the Debian Bullseye freeze.
