This guide can help you upgrade elementary OS 7.1 to version 8 by entering commands into the Terminal. Currently tested only on my computer. Write in the comments about successful and unsuccessful upgrade attempts using this guide.

elementary OS 7.1 to 8 upgrade using Terminal

## (It may not be that easy, especially if errors occur.
## I think I've written in enough detail, if it's hard for you to understand what's going on here, maybe you should stop.
## Perhaps an AI chatbot can be useful if you send him these instructions.
## You may want to consider switching to a distribution that supports upgrades between versions:
## Ubuntu, Zorin, Pop_OS, Mint, Endless OS)

#!!! IMPORTANT STEP FOR NVIDIA GPU USERS !!!
#! If you don't remember the model of your GPU.
#! Run this command and see if there is a line containing "Nvidia"
lspci -v | egrep -i --color 'vga|3d|2d'
# Prep: Check that your Nvidia GPU is supported by Elementary 8
# Go to the Nvidia Drivers Download page ( https://www.nvidia.com/en-us/drivers/ )
# Find yours GPU in "Manual Driver Search" and select "Linux 64-bit" OS
# Click "Find". On driver download page, check "Driver Version" not less than 470.
# If version 390 or less, do not proceed. Otherwise, you'll end up with an internal GPU or a black screen.
# There are guides on the Internet on how to install Elementary 8 (Ubuntu 24.04) with old Nvidia drivers, but they require more steps and knowledge.


# Prep: Update OS 7.1 system and reboot system
sudo apt update && sudo apt upgrade -y && sudo apt dist-upgrade -y && sudo apt autoremove -y
flatpak update -y
sudo reboot

# Use the root shell for the following commands
sudo -i
# Enter your password if required 

# Remove old Pantheon Tweaks PPA
# (now distributed via flatpak)
add-apt-repository --remove ppa:philip.scott/pantheon-tweaks
# Press ENTER
# Remove dead Ubuntu Partner repository
sed -e '/archive.canonical/ s/^#*/#/' -i /etc/apt/sources.list
# Use repositories from OS 8
grep -rl 'jammy' /etc/apt/ | xargs sed -i 's/jammy/noble/g'
# Update packages from new repositories
apt update && apt upgrade -y && apt dist-upgrade -y && apt autoremove -y

# Remove Snap
apt purge snapd ubuntu-core-launcher squashfs-tools
rm -rf ~/.snap
rm -rf /var/snap
rm -rf /var/lib/snapd
apt-mark hold snapd

reboot


flatpak update -y

# Clear unused flatpak packages
flatpak delete --unused -y

# Use the root shell for the following commands
sudo -i
# Enter your password if required 

# Remove old kernels
apt remove -y linux-image-5.15*
apt autoremove -y

# OPTIONAL. Read the description
# Check the tray: On the right should be icons for WIFI/internet, sound, notifications, and quick settings.
# (Example: https://i0.wp.com/9to5linux.com/wp-content/uploads/2024/11/eos8.webp )
# Check the settings: each item should open, the application should not crash.
# IF EVERYTHING IS WORKING, SKIP THIS STEP AND JUST REBOOT.

# IF NOT, try to run the commands below
# (This item is new and may cause problems. 
# Send your error to the AI chatbot to solve it quickly.
# And don't forget to write about this error in the comments so that I can improve this guide.)
  sudo -i
  apt remove -y wingpanel*
  apt install -y wingpanel* io.elementary.*
  apt remove -y io.elementary.settings-mouse-touchpad io.elementary.installer*
  apt --fix-broken install
  apt autoremove -y
# 

reboot

## DONE

I tried this in a fresh 7.1 VM and had to update to a newer kernel: sudo apt-get install --install-recommends linux-generic-hwe-24.04. I didn't have to do the "Fix tray" settings.

Aptitude showed 25-30 obsolete or local packages that were no longer provided by the apt source, I removed them to see what happens, you might want to go through them one by one.

To update the flatpak extensions:

flatpak remove org.freedesktop.Platform.GL.default     # Select all
flatpak install org.freedesktop.Platform.GL.default --system   # Select flathub, then 24.08
flatpak install org.freedesktop.Platform.GL.default --system   # Select flathub, then 23.08

flatpak remove io.elementary.Platform # Select any 7.x versions, I also had to uninstall tasks.

The instructions now include steps to clean up some flatpak packages and old kernels.
Also, the tray fixing step is now optional.

I'm thinking about upgrading from 7.1 to 8 by using this guide? This still works? :)

It's unlikely that anything will change here. But it won't be as simple as clicking the update button.

Why do you remove snap?

Elementary uses Flatpak instead of Snap. Unlike Ubuntu, which it is based on. So if you update manually, Snap will be installed. Since it is not integrated with the system and is unlikely to be used, we will remove it.
(Actually, I just copied these lines from the 5 to 6 update guide)

Hi everyone! I did something like this (can't remember all the steps), when I upgraded from 6 to 7, and didn't have to backup all my data. Does this method requires to backup all my stuff ?

It's an unsupported and untested in the real world way to upgrade elementaryOS, so definately yes.

Ok so I ran this on my workstation, after using Timeshift to create a restore point. The AMD GPU drivers caused kernel build failures, so I used this guide to remove them, and I will install them freshly now that I've upgraded.

Also my custom shortcuts were all deleted, so I'd recommend to back them up before hand.

Added Nvidia driver check to the instructions.
Let's not count on reclockable Nouveau.