ERR_NETWORK_CHANGED on linux mint

Your connection was interrupted

A network change was detected.

ERR_NETWORK_CHANGED

Temporarily Disable IPv6: Run:

sudo sysctl -w net.ipv6.conf.all.disable_ipv6=1
sudo sysctl -w net.ipv6.conf.default.disable_ipv6=1

Test browsing and downloading for 5-10 minutes. If the issue stops, make it permanent by editing GRUB and modify the GRUB_CMDLINE_LINUX_DEFAULT line to include ipv6.disable=1

sudo vi /etc/default/grub

...
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash ipv6.disable=1"
...

sudo update-grub

Reboot and verify IPv6 is disabled:

ip a | grep inet6

No output means IPv6 is off.