I've followed the steps to add the QR code cordova plugin to my Ionic4/Angular/Capacitor app, but can't get it to work (in a web/pwa context, or on device on android).

After adding the cordova plugin and associated angular package/import and running 'npx capacitor sync', I can see the plugin in the list:

√ Copying capacitor.config.json in 1.91ms
Found 7 Cordova plugins for android
CordovaPluginDevice (2.0.2)
CordovaPluginFile (6.0.1)
CordovaPluginFileTransfer (1.7.1)
CordovaPluginIonic (5.2.10)
CordovaPluginQrscanner (2.6.0)
CordovaPluginWhitelist (1.3.3)
CordovaSqliteStorage (2.6.0)
√ copy in 1.48s

And my code is a copy and paste from the docs, I'm importing the QR scanner:

import { QRScanner, QRScannerStatus } from '@ionic-native/qr-scanner/ngx';

Injecting it into my angular component:

constructor(private qrScanner: QRScanner)

And I've got got a button that calls this function:

` qrScan() {
// Optionally request the permission early
this.qrScanner.prepare()
.then((status: QRScannerStatus) => {
if (status.authorized) {
// camera permission was granted

      // start scanning
      const scanSub = this.qrScanner.scan().subscribe((text: string) => {
        console.log('Scanned something', text);

        this.qrScanResult = text;

        this.qrScanner.hide(); // hide camera preview
        scanSub.unsubscribe(); // stop scanning
      });

    } else if (status.denied) {
      // camera permission was permanently denied
      // you must use QRScanner.openSettings() method to guide the user to the settings page
      // then they can grant the permission from there
      console.log('denied');
    } else {
      // permission was denied, but not permanently. You can ask for permission again at a later time.
    }
  })
  .catch((e: any) => console.log('Error is', e));

}`

But after an ionic build and an npx sync, this doesn't work. Clicking the button does nothing.
In a browser with 'npx cap serve' the error is that it can't find Cordova. Do cordova plugins that support 'browser' work in a capacitor context?

With 'npx cap open android' in android studio running debug on the phone, the button also does nothing, but I'm too much of a n00b to know where error output would appear, but happy to follow instructions to give more detail.