Push Notifications Background Handler

At the moment I am using Firebase and Capacitor APIs for Push and Local Notifications.
After reading into the subject of notifications and the differences between Data & Display notifications I am at a roadblock.

What I would like to achieve is to send a data notification from a Cloud Function on Firebase that is then presented to the user when the app is in the background (dead or inactive), a key feature being that a user can reply inline with this notification - like you can do on any chat application.

I can partially achieve this by sending data notifications, listening for them with with Push Notification API

PushNotifications.addListener('pushNotificationReceived' => (notification: PushNotification) => {})

And then displaying them with the local notification API.

async showNativeNotification(data: any) {

        if ((await App.getState()).isActive) {
            console.log('Application Open - Notification Suppressed', data);

        let notifTitle = 'Knapsack';
        const prefColour = await this.prefService.getPreferences();
        if (data.location) {
            notifTitle = `${data.location.topic.name} - ${data.location.workspace.name}`;

            notifications: [{
                id: 1,
                title: notifTitle,
                body: `${data.sender ? `${data.sender.name}: ` : ''}${data.message.snippet}`,
                attachments: null,
                iconColor: prefColour.userPrefs.theme ? UtilityHelper.themePropToHex(prefColour.userPrefs.theme.properties.primary) : '#f74258',
                actionTypeId: 'chat_message',
                extra: data


Actions Being Registered Earlier in the App:

                types: [
                        id: 'chat_message',
                        actions: [
                                id: 'mute',
                                title: 'Mute',
                                destructive: true,
                                foreground: true
                                id: 'reply',
                                title: 'Reply',
                                input: true,
                                destructive: true,
                                foreground: false,
                                inputPlaceholder: 'Ab',
                                inputButtonTitle: 'Send'

This produces the exact thing I would like when the app is in the background somewhere.
However the issue is as it’s a data notification this function never fires when the app is completely killed.

If i send a display notification however then this comes through fine when the app is inactive & when the app has been killed, however to my knowledge there is no way of allowing input onto these, and registering events. Am I missing something or is this purley something that doesn’t exist at the moment?

I can make to with the boring un-interactive notifications but would love more flexibility. Any information or help on this topic would be much appreciated.