Slackware, Gentoo, the Mandriva family (OpenMandriva, Mageia, PCLinuxOS, ROSA, ALT Linux), Void, Alpine, Chimera, Venom, CRUX, Exherbo, Paldo, the PiSi family (PiSi Linux, old versions of Pardus), and Solus (eopkg is a fork of PiSi).
🏴 Ringtons (a personal favourite) is popular in and around Newcastle, where the company is based.
🏴 Yorkshire Tea (also exceedingly popular in the north as well as the midlands) is owned by Betty's & Taylors.
🇬🇧 Tetley is a popular brand owned by 🇮🇳 Tata, though personally I can't drink the stuff.
Coffee
🏴 Black Sheep Coffee is a chain of coffee shops in the UK, but they also sell beans and grounds.
🏴 Pilgrims Coffee is a small roastery on Holy Island.
While their instant coffee is never great, supermarket own-brand beans and grounds are better than you would expect. 🇬🇧 Tesco and 🇬🇧 Waitrose both sell fairly nice coffee.
🏴 Pumphrey's is another small coffee roaster, from Newcastle-Upon-Tyne. Many independent cafés and shops in the north-east sell their coffee, but I believe you have to buy beans and grounds directly.
🏴 Red Box Coffee is based in Edinburgh and they sell tea and coffee, both of which are quite nice.
Obviously check out Eylenburg's page and the ArchWiki, but here are my two cents on a bunch of DEs:
GNOME
Not particularly customisableCan be customised heavily, but the settings aren't exposed and the devs don't like it much.KDE Plasma
KDE Liquid
Xfce
LXQt
LXDE
MATE
Cinnamon
Budgie
deepin
Trinity
Enlightenment
COSMIC
Lumina
Pantheon
CDE
FVWM-Crystal