[Fixed] An Unexpected Error Occurred on Gnome Extensions

Are you also encountering the annoying "An unexpected error occurred" message (or notification) when visiting the Gnome extensions site, even after installing the supporting browser extension and connector?

Then you've come to the right place, as I'm about to provide you with multiple solutions to fix this issue.

📝 Note

If you're operating an Ubuntu system, try following the fourth step mentioned in this article, as it often resolves the issue.

Table of Contents

How to Fix an Unexpected Error Problem With Gnome Extensions

There could be multiple reasons for this error, and since there is no clear indication of the cause, you need to apply multiple solutions to fix this issue.

Now, here I've provided you with a handpicked solution for this error that you can apply immediately to fix these issues, starting with.

Fix 1: Restart Your System

It might be possible that you are trying to access the Gnome Extensions webpage just after installing its browser extensions and connector. Now, there is no issue with directly accessing the webpage, as most of the time it works flawlessly. But if you encounter the error, then simply rebooting and rechecking is worth it.

Fix 2: Reinstall the Browser Extension and Connector

Either a sudden version change or an interruption during installation of the connector could occur; thus, removing the existing one and reinstalling it might resolve these issues.

So, first remove the existing connector by executing the following command:

Run this command on Ubuntu 23.04 or newer
sudo apt --purge remove gnome-browser-connector
Run this command on Ubuntu 22.04 or older
sudo apt --purge remove chrome-gnome-shell

Then reinstall it by running the following command:

How to Setup GNOME Shell Extensions on Ubuntu and Other Linux Distros

Run this command on Ubuntu 23.04 or newer
sudo apt install gnome-browser-connector
Run this command on Ubuntu 22.04 or older
sudo apt install chrome-gnome-shell

Once the installation is complete, remove the "GNOME Shell integration" browser extension, then reinstall it for Firefox or Chrome, and revisit the Gnome Extensions site to verify that the error has been resolved.

Fix 3: Updating the System

If the error persists, update your system repository information for the latest package and upgrade the packages to their latest version.

Updating the Repository Information
sudo apt update
Upgrading the Packages
sudo apt upgrade

Fix 4: Switch to a Different Browser

This solution works most of the time on Ubuntu or any other Linux distribution that uses the Firefox Snap variant by default, as the cause of this error is suspected to be the issues with the permission restriction set to Snap packages.

To resolve this, you can either remove the Firefox Snap package and install it using the distribution package or use another browser outside of the sandbox technology.

1. Install Firefox Distribution Package

So, if you want to remove the Firefox Snap package and install it using the DEB package on your Ubuntu system, then follow these steps:

How to Install Firefox as a DEB Package on Ubuntu (No Snap)

Removing the Firefox Snap
sudo snap remove firefox
Create an APT keyring (if one doesn’t already exist)
sudo install -d -m 0755 /etc/apt/key
Import the Mozilla APT repo signing keyrings
wget -q https://packages.mozilla.org/apt/repo-signing-key.gpg -O- | sudo tee /etc/apt/keyrings/packages.mozilla.org.asc > /dev/null
Add the Mozilla signing key to your sources.list
echo "deb [signed-by=/etc/apt/keyrings/packages.mozilla.org.asc] https://packages.mozilla.org/apt mozilla main" | sudo tee -a /etc/apt/sources.list.d/mozilla.list > /dev/null

Once you have finished adding the Mozilla APT repository and signing key, then run the following command to always prioritize the Firefox distribution package over Snap:

echo 'Package: *
Pin: origin packages.mozilla.org
Pin-Priority: 1000' | sudo tee /etc/apt/preferences.d/mozilla

Finally, execute the following command to install Firefox:

sudo apt update && sudo apt install firefox

Once the installation is done, open the Firefox browser, install the "Gnome Shell Integration" extension, and recheck the Gnome Extensions webpage.

2. Install Chrome Distribution Package

If you prefer not to remove the Firefox Flatpak package and wish to try another browser, considering Chrome wouldn't be a bad idea. So, follow the below steps to install Google Chrome using the DEB package on your Ubuntu system.

sudo apt install wget curl
wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb
sudo dpkg -i google-chrome-stable_current_amd64.deb
sudo apt install -f

Once the installation is done, open the Chrome browser, install the "Gnome Shell Integration" extension, and recheck the Gnome Extensions webpage.

Fix 5: Test with a New User Account

If the previous solution is not solving the issue, then create a new user account on your system, switch to it, install the browser extension and connector, and check the Gnome Extensions site for the status.

If the error is resolved, there's likely an issue with your other user account; otherwise, there are issues with the packages on the system. In that case, you can try seeking help on AskUbuntu.

Fix 6: Manual Installation of Extensions

Finally, if none of the above-mentioned methods work, then for the time being, you are only left to install your favorite Gnome extension manually, the steps of which are usually mentioned on the GitHub link provided on each Extension page.

For example, the WTMB (Window Thumbnails) extension has a GitHub link next to "Extension Homepage".

looking for github link on gnome extension page

When you visit its GitHub page, scroll to the installation section, and you will be provided with the installation steps that you can easily follow to install it on your system.