While it doesn't appear to be affecting anything other than my web performance, does anyone have any idea what this means or how to fix it:

Nov 24 12:34:06 unRaid nginx: 2020/11/24 12:34:06 [crit] 10774#10774: *9985 connect() to unix:/var/tmp/plex.sock failed (2: No such file or directory) while connecting to upstream, client: 172.18.122.25, server: , request: "GET /dockerterminal/plex/token HTTP/1.1", upstream: "http://unix:/var/tmp/plex.sock:/token", host: "unraid.local", referrer: "http://unraid.local/dockerterminal/plex/"
Nov 24 12:34:06 unRaid nginx: 2020/11/24 12:34:06 [crit] 10774#10774: *10439 connect() to unix:/var/tmp/plex.sock failed (2: No such file or directory) while connecting to upstream, client: 172.18.122.25, server: , request: "GET /dockerterminal/plex/ws HTTP/1.1", upstream: "http://unix:/var/tmp/plex.sock:/ws", host: "unraid.local"

I tried creating plex.sock and I've tried re-mapping /var/tmp to nobody:user instead of root:root, but to no avail. Here's what my /var/tmp looks like:

root@unRaid:/var/tmp# ls -l
total 28
-rwxrwxrwx 1 root root   104 Nov 24 11:46 go*
-rw-rw-rw- 1 root root   652 Nov 24 12:18 ident.cfg
-rw-rw-rw- 1 root root 18747 Nov 24 11:47 unRAIDServer.txt
root@unRaid:/var# ls -l
total 0
lrwxrwxrwx  1 root root   3 Mar  5  2020 adm -> log/
drwxr-xr-x  5 root root 100 Nov 24 11:45 cache/
drwxr-xr-x  2 root root  40 Nov 24 11:45 empty/
drwxr-xr-x 17 root root 340 Mar  5  2020 lib/
drwxr-xr-x  3 root root  60 Mar  5  2020 local/
drwxrwxrwt  3 root root  60 May  2  2010 lock/
drwxr-xr-x  9 root root 560 Nov 24 11:46 log/
lrwxrwxrwx  1 root root  10 Mar  5  2020 mail -> spool/mail/
drwxr-xr-x  8 root root 740 Nov 24 12:18 run/
drwxr-xr-x  2 root root  60 Nov 24 11:47 sa/
drwxr-xr-x  8 root root 160 Dec 18  2019 spool/
drwxr-xr-x  5 root root 100 Nov 24 11:46 state/
drwxrwxrwt  2 root root 100 Nov 24 12:31 tmp/
drwxr-xr-x  2 root root  40 Mar  5  2020 www/

Does anyone have any idea what may have caused this and how to fix it?

It actually looks like it's only an issue in Brave, not Safari, so I guess it's a browser compatibility issue. Only just started, though-I'd been running things fine for the past week...