We follow the principle of doing one thing well instead of all things mediocre, so we use 2 solutions for what you asked. As others in the thread, we do use Tandoor, but only for Recipes and Meal Planning. It does this execeptionally well, but the shopping list part is fitting to our style of shopping.

As a shopping list, we use David Shays Groceries / Specifically Clementines. Why?

• It works offline when you are in one of those huge buildings that work like a faradays cage and you do not have reception anymore.
• It lets my partner attach a picture to a list item, so I can find that specific cheese when I am standing clueless in front of those shelves with 500 different cheese brands and that helps me find the right item before the shop closes.
• It works exactly the way we shop. We always arranged items in the order they are in the shop when you work through the shop from entry to exit. That is super efficient.
• It supports aisles. That means your items are assigned to an aisle. The super cool feature here is, that you can rearrange the isles for each shop. Veggies are at the entrance of Shop A, but at the middle of Shop B? Just arrange the isle for Shop A to the start of the list and to the middle of Shop B. Since all items are connected to an isle, they move with the aisle. This way you never have to turn around in a shop to get “those other things”. You just walk from entry to exit in one line and be done with it.
• With this software I never forgot to buy something I did not find in Shop A. How this software does it is that you create list groups that contain lists for every shop that fits. For example you group food shops together, or shops for gardening stuff. Within the list groups, you have your items. And when putting an item on a list, you can select on which list it should appear. Now when you put your favourite cheese on the List of Shop A and B and you bought it on Shop A, it gets ticked off on Shop B too. Or the other way round, I think you get the idea.
• I have to repeat that it works offline. A shopping list is useless if you can not use it when you are shopping.
• Accidentially ticked off an item because, well… touchscreens and you do not know what it was? No problem. Ticked off items just move down that list and you can pick it up again. With other apps stuff just disappears or gets send back to the global item list and now you do not have any idea what you missed. Not so with “Specifically Clementines”.
• It never let us down. It always worked, whether offline or online without any hiccups.

There is more, but this post got too long already. It also has User Management, Permissions and Live Sync. Yes, my Partner can see live when I tick of items on the list and can put stuff on the list while I am shopping :-)

Everything in that software feels like it was created by a person that goes actually shopping.

It has a very good web interface (which also has the offline mode AFAIK) and a very good Android App.

Does it look fancy? No. Has it everything we ever searched for in a shopping list app? Absolutely!

Could it be an MTU issue? Networking van be weird if packets get fragmented unexpectedly, but I see this mostly for IKEv2 and other VPN Services. Try to lower your MTU on the WAN side Maybe?

I run Nextcloud for many, many years. I hosted it for a very long time at Hetzners second lowest tier of Webspace they rent. It was not very fast there (you get what you pay for), but fast enough for our need here. Later I moved it to an Azure VM and after that to my Homeserver where it runs blazingly fast, especially since the last updates they pushed out.

In all that time I never reinstalled. I just upgraded to the newer versions when they were out. The only times I had problems upgrading was when I was hosting at the cheap Webspace instance at Hetzner and an upgrade process took longer than the PHP timeout my very cheap hosting instance provided. So it was never a fault of Nextcloud, but just that I hosted it on basically the cheapest hosting plan I could find.

We use it for file sharing, calendar + contacts (+ Sync with DAVx), Notes and of course Talk. For talk to make full use of Voice + Video calls, you should have a TURN Server, but if you do not use that (if you just text) it was running great even on the Webspace instance at Hetzner.

We are very happy in our family that it exists, that it is free and that it serves us well since many years.

You would think so, yes. But to my surprise, my well over 60 Containers so far consume less than 7 GB of RAM, according to htop. Also, of course Containers can network and share services. For external access for example I run only one instance of traefik. Or one COTURN for Nextcloud and Synapse.

I would absolutely look into it. Many years ago when Docker emerged, I did not understand it and called it “Hipster shit”. But also a lot of people around me who used Docker at that time did not understand it either. Some lost data, some had servicec that stopped working and they had no idea how to fix it.

Years passed and Containers stayed, so I started to have a closer look at it, tried to understand it. Understand what you can do with it and what you can not. As others here said, I also had to learn how to troubleshoot, because stuff now runs inside a container and you don´t just copy a new binary or library into a container to try to fix something.

Today, my homelab runs 50 Containers and I am not looking back. When I rebuild my Homelab this year, I went full Docker. The most important reason for me was: Every application I run dockerized is predictable and isolated from the others (from the binary side, network side is another story). The issues I had earlier with my Homelab when running everything directly in the Box in Linux is having problems when let´s say one application needs PHP 8.x and another, older one still only runs with PHP 7.x. Or multiple applications have a dependency of a specific library when after updating it, one app works, the other doesn´t anymore because it would need an update too. Running an apt upgrade was always a very exciting moment… and not in a good way. With Docker I do not have these problems. I can update each container on its own. If something breaks in one Container, it does not affect the others.

Another big plus is the Backups you can do. I back up every docker-compose + data for each container with Kopia. Since barely anything is installed in Linux directly, I can spin up a VM, restore my Backups withi Kopia and start all containers again to test my Backup strategy. Stuff just works. No fiddling with the Linux system itself adjusting tons of Config files, installing hundreds of packages to get all my services up and running again when I have a hardware failure.

I really started to love Docker, especially in my Homelab.

Oh, and you would think you have a big resource usage when everything is containerized? My 50 Containers right now consume less than 6 GB of RAM and I run stuff like Jellyfin, Pi-Hole, Homeassistant, Mosquitto, multiple Kopia instances, multiple Traefik Instances with Crowdsec, Logitech Mediaserver, Tandoor, Zabbix and a lot of other things.