How to fix W: Changing to experimental distribution. This will likely break things! in APT

Experimental packages are unmaintained, untested, and can break your system. Only use experimental if you understand package management and can troubleshoot issues. If you're unsure, consider using testing (which receives security updates) instead of experimental.

Create /etc/apt/preferences.d/experimental to pin specific packages from experimental while keeping your system stable:

Package: package-name
Pin: release a=experimental
Pin-Priority: 600

Replace package-name with the specific package you need. Pin-Priority 600 overrides the default (1) but stays below auto-upgrades (1000).

Once pinning is configured, install the package:

sudo apt update
sudo apt install package-name

APT will now allow installation from experimental while respecting your pinning priority.

After installation, test the package extensively. Check for:
- Missing features or broken functionality
- Dependency conflicts with other installed packages
- Performance or stability regressions
- Security implications

If the package causes problems, you can remove it with sudo apt remove package-name.

If you only needed one experimental package, remove the experimental repository from your sources.list to reduce accidental breakage:

# Edit /etc/apt/sources.list or remove from sources.list.d
sudo rm /etc/apt/sources.list.d/experimental.list
sudo apt update

Keep pinning in place for packages already installed from experimental.