Fix ERR_NETWORK_CHANGED in Chrome and Brave on Ubuntu While Firefox Works

The Problem: Chrome and Brave Show ERR_NETWORK_CHANGED on Ubuntu

I encountered a strange network issue on my Ubuntu machine. While browsing in Google Chrome and Brave, I frequently received an interruption saying that a network change was detected.

Your connection was interrupted
A network change was detected.
ERR_NETWORK_CHANGED

The interesting part was that Firefox worked perfectly on the same machine and office Wi-Fi network.

• Google Chrome frequently displayed ERR_NETWORK_CHANGED.
• Brave showed the same error.
• Firefox worked without any noticeable issue.
• The error occurred randomly while browsing.
• Pages usually recovered or reloaded automatically.
• The Ubuntu laptop was connected to office Wi-Fi.

I initially suspected that the office Wi-Fi or DHCP server was frequently changing my IP address. Further investigation pointed to another possible cause: Docker networking on Ubuntu.

Why Was Firefox Working While Chrome and Brave Were Failing?

Chrome and Brave both use the Chromium browser engine, while Firefox uses its own networking implementation. Chromium monitors network configuration changes, including network interfaces, IP addresses, routing tables, DNS configuration, and connectivity state.

When Chromium detects certain changes, it may close existing connections and establish new ones. That can surface as ERR_NETWORK_CHANGED. Firefox handles these events differently and may recover without showing an error.

The Possible Root Cause: Docker Virtual Network Interfaces

Docker creates virtual networking components so containers can communicate with one another and reach external networks.

When containers start, stop, or connect to networks, Docker may create, modify, or remove these interfaces. Those operations generate network-related events in the Linux kernel. Under some conditions, Chromium may interpret the events as a network configuration change.

This could explain why Chrome and Brave were affected while Firefox continued to work. Simply having Docker installed does not guarantee this problem; behavior depends on Docker's networking configuration, Linux networking components, and Chromium's response to those events.

Diagnostic Test: Temporarily Stop Docker

Step 1: Stop the Docker Service

Open a terminal and stop both the Docker daemon and its socket on a typical systemd-managed Docker Engine installation.

sudo systemctl stop docker.service docker.socket

Step 2: Verify That Docker Is Stopped

systemctl is-active docker.service docker.socket

The expected output is inactive for both units.

inactive
inactive

Step 3: Test Chrome and Brave

After stopping Docker, I continued browsing in Chrome and Brave. The frequent ERR_NETWORK_CHANGED errors appeared to stop, while Firefox continued working normally.

How to Confirm Whether Docker Is Responsible

Stopping Docker and seeing an improvement is useful evidence. To build a stronger case, compare Linux network events, Docker activity, and the time the browser error occurs.

1. Monitor Network Changes

ip -ts monitor all

Look for interface, address, or route activity involving docker0, br-*, and veth*.

2. Monitor Docker Events

docker events

3. Compare the Events

While both commands are running, browse normally in Chrome. If ERR_NETWORK_CHANGED appears, check whether Docker and Linux network events occurred at approximately the same time.

12:30:15 - Docker container starts
12:30:15 - Virtual network interface created
12:30:16 - Chrome displays ERR_NETWORK_CHANGED

If this pattern repeats consistently, it is stronger evidence that Docker-related network changes are triggering the browser error. Chromium's chrome://net-export/ page can also capture network events for analysis.

How to Restart Docker After Testing

sudo systemctl start docker.socket docker.service

Verify the service and start individual containers again if your configuration requires it.

systemctl is-active docker.service

The expected output is active. Continue browsing in Chrome and Brave after the restart. If the error returns and disappears again when Docker is stopped, the connection becomes more convincing.

What If You Need Docker Running All the Time?

Stopping Docker is a useful diagnostic test and temporary workaround, not necessarily a permanent solution. If Docker is required for daily development, investigate the specific networking event responsible.

1. Check for containers that repeatedly restart with docker ps -a.
2. Inspect custom bridge networks with docker network ls and watch for frequent connects or disconnects.
3. Use nmcli device status to see whether NetworkManager is managing Docker-created interfaces unnecessarily.
4. Investigate IPv6-related events on virtual Ethernet interfaces, but do not disable IPv6 globally without evidence.
5. Use Chromium network logs to identify the exact configuration event that triggers the interruption.

The permanent fix depends on the underlying cause. Docker, Kubernetes, VPNs, and other applications can all create or modify virtual network interfaces, so keep the investigation evidence-driven.

Final Result

After stopping Docker on Ubuntu, Chrome and Brave appeared to work normally without the frequent ERR_NETWORK_CHANGED errors. Firefox continued to work throughout the test.

This suggests that Docker-related networking was a likely contributor. Additional monitoring after restarting Docker is still required to confirm the exact event and establish a permanent fix.

Conclusion

ERR_NETWORK_CHANGED in Chrome and Brave does not always mean the internet connection itself is unstable. On Linux systems running container tools, virtual network changes may contribute to the error.

If Chrome and Brave frequently fail on Ubuntu while Firefox works normally, do not immediately assume Wi-Fi or DHCP is responsible. Checking Docker networking first may save time otherwise spent troubleshooting the router, browser cache, or office network.