Comment 6 for bug 1866659

For English (US) on hirsute, here's the missing packages:

hyphen-en-gb
libreoffice-help-en-us
libreoffice-l10n-en-za
gimp-help-en
thunderbird-locale-en
libreoffice-help-en-gb
wbritish
thunderbird-locale-en-gb
libreoffice-l10n-en-gb
hunspell-en-za
hunspell-en-au
mythes-en-au
hyphen-en-us
thunderbird-locale-en-us
hyphen-en-ca
mythes-en-us
hunspell-en-gb
hunspell-en-ca

It looks like ubuntu automatically includes these files for a select number of languages.
https://people.canonical.com/~ubuntu-archive/seeds/ubuntu.hirsute/ (see the languages directory).

Should Xubuntu do the same?