I confirmed the solution provided by @chandradeepdey on a fresh VM install with the archinstall script's default networking option selected (this is as close to a "default" configuration as possible, although most users are probably still used to configuring their network manually during install). Removing resolve [!UNAVAIL=return] from /etc/nsswitch.conf fixes the issue even with systemd-resolved running (no restart required). Someone in the chromium thread also pointed out that this is specific to a combination of systemd-resolved and libnss_resolve.
@chandradeepdey also brings up a good point regarding security. Given everything we know about this issue right now, I don't think the update should continue to be blocked. There should be a post_install function in this package which notifies users of the problem with resolved+libnss in the current version.
Pinned Comments
alerque commented on 2021-11-27 03:11 (UTC)
@ant0n et all, lets keep the comments here about packaging issues, general Brave usage issues should go in another forum to not clutter up this comment space. I'm deleting comments that have no relation to packaging. Grey areas like crashes that could be blamed on Arch can stay until proven otherwise, but things like how to configure Brave to handle popups or site X or whatever just don't belong here. Thanks for understanding.