Fails to download installer if `LANG=C`

[paulmenzel]

Trying to install/update nightly with LANG=C fails, as the installer can’t be downloaded.

$ sudo LANG=C apt full-upgrade
The following packages will be upgraded:
  nightly
1 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B/226 kB of archives.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] 
(Reading database ... 414409 files and directories currently installed.)
Preparing to unpack .../nightly_89.0a1+_all.deb ...
C
Current Language is ⁝C⁝ = ⁝C⁝
--2021-03-29 07:24:26--  https://download.mozilla.org/?product=firefox-nightly-latest-l10n-ssl&os=linux64&lang=C
Resolving download.mozilla.org (download.mozilla.org)... 52.2.180.238, 34.198.56.245, 18.214.2.56
Connecting to download.mozilla.org (download.mozilla.org)|52.2.180.238|:443... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://download-installer.cdn.mozilla.net/pub/firefox/nightly/latest-mozilla-central-l10n/firefox-89.0a1.C.linux-x86_64.tar.bz2 [following]
--2021-03-29 07:24:26--  https://download-installer.cdn.mozilla.net/pub/firefox/nightly/latest-mozilla-central-l10n/firefox-89.0a1.C.linux-x86_64.tar.bz2
Resolving download-installer.cdn.mozilla.net (download-installer.cdn.mozilla.net)... 2600:9000:21a1:7000:e:19d6:1546:5981, 2600:9000:21a1:1e00:e:19d6:1546:5981, 2600:9000:21a1:ee00:e:19d6:1546:5981, ...
Connecting to download-installer.cdn.mozilla.net (download-installer.cdn.mozilla.net)|2600:9000:21a1:7000:e:19d6:1546:5981|:443... connected.
HTTP request sent, awaiting response... 404 Not Found
2021-03-29 07:24:27 ERROR 404: Not Found.

dpkg: error processing archive /var/cache/apt/archives/nightly_89.0a1+_all.deb (--unpack): new nightly package pre-installation script subprocess returned error exit status 8
Errors were encountered while processing: /var/cache/apt/archives/nightly_89.0a1+_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

[Vitexus]

New version do not crash with LANG=C