function installExtension -d "Installs a Chromium extension for the browser with the specified information" -a name dir bin policyDir extensionDir
    [ -n "$bin" ]
    or set -l bin google-chrome-stable
    [ -n "$policyDir" ]
    or set -l policyDir /opt/google/chrome/extensions
    [ -n "$extensionDir" ]
    or set -l extensionDir /usr/local/share/chromium-extensions

    set -l keyFile "$dir.pem"
    set -l extensionFile "$dir.crx"
    set -l manifestFile "$dir/manifest.json"
    set -l destination "$extensionDir/$name.crx"

    rm "$keyFile" &>/dev/null
    $bin --pack-extension="$dir"

    # Tamper manifest file
    begin
        set -l manifest (cat "$manifestFile" | KEY=(openssl rsa -in "$keyFile" -pubout -outform DER | openssl base64 -A) jq ". + { key: env.KEY }")
        echo "$manifest" >"$manifestFile"
        $bin --pack-extension="$dir" --pack-extension-key="$keyFile"
    end

    set -l id (openssl rsa -in "$keyFile" -pubout -outform DER | sha256sum | head -c32 | tr 0-9a-f a-p)
    set -l extVersion (cat "$manifestFile" | jq -r ".version")

    # Install and configure extension
    begin
        set -l property external_crx
        sudo mkdir -p "$extensionDir"
        sudo cp "$extensionFile" "$destination"
        sudo chmod -R a+rx "$extensionDir"
        sudo chmod -R u+w "$extensionDir"
        sudo mkdir -p "$policyDir"

        for manifest in (find "$policyDir" -name "*.json" -print0 | string split0 || true)
            if [ (cat "$manifest" | jq -r ".$property") = "$destination" ]
                sudo rm "$manifest"
            end
        end

        begin
            echo null | \
                FILE="$destination" \
                VERSION="$extVersion" \
                jq '{ external_crx: env.FILE, external_version: env.VERSION }'
        end | sudo tee "$policyDir/$id.json" >/dev/null
    end
end