Firefox startpage script for /wg/

#!/bin/bash

set -e

me=$(basename "$0")

# Making sure the script has root privileges
if [ $EUID -ne 0 ]
then
    echo "$me: Setting a startpage requires root privileges."
    exec sudo "$0" "$@"
fi

firefox_dir="/usr/lib/firefox-esr"
firefox_autoconfig="$firefox_dir/defaults/pref/autoconfig.js"
firefox_startpage_config="$firefox_dir/startpage_config.js"

if [ $# -eq 0 ]
then
    echo "$me: No startpage specified."
    exit 1
elif [ $# -gt 1 ]
then
    echo "$me: Avoiding all arguments except the first one."
fi

startpage="$(realpath $1)"

if [ ! -f "$startpage" ]
then
    echo "$me: Cannot set startpage '$startpage': No such file exists."
    exit 1
fi

cat << EOF > $firefox_autoconfig
pref("general.config.filename", "$(basename $firefox_startpage_config)");
pref("general.config.obscure_value", 0);
EOF

echo "$me: Successfully written to '$firefox_autoconfig'."

cat << EOF > $firefox_startpage_config
const { classes:Cc, interfaces:Ci, utils:Cu } = Components;

const startpageURL = "file://$startpage";

try
{
    ChromeUtils.defineESModuleGetters(this, {
        AboutNewTab: "resource:///modules/AboutNewTab.sys.mjs",
        HomePage: "resource:///modules/HomePage.sys.mjs"
    });

    AboutNewTab.newTabURL = startpageURL;
    HomePage.safeSet(startpageURL);
}
catch(e)
{
    Cu.reportError(e);
}
EOF

echo "$me: Successfully written to '$firefox_startpage_config'."

echo "$me: Successfully set startpage as '$startpage'."