For example, under <https://www.freebsd.org/search/#mailinglists> seek:
installworld single user mode
* the first, and fourth results are from FreeBSD Forums (not a list).
(I don't scroll further.)
A few days ago I stumbled across what _might_ have been a comparable bug, fixed, which mentioned something like, DuckDuckGo (DDG) no longer searching multiple domains.
Today I can't find that bug; sorry.