GNOME Shell 45 moved to ESM (ECMAScript modules). That means you MUST use the standard import declaration instead of relying on the previous imports.* approach.
https://gjs.guide/extensions/upgrading/gnome-shell-45.html
So the imports in your extensions is changed from:
const Clutter = imports.gi.Clutter;
const Gio = imports.gi.Gio;
const Main = imports.ui.main;
const Volume = imports.ui.status.volume;
to
import Clutter from 'gi://Clutter';
import Gio from 'gi://Gio';
import * as Main from 'resource:///org/gnome/shell/ui/main.js'
import * as Volume from 'resource:///org/gnome/shell/ui/status/volume.js';