[DEPRECATED] Sample code on how to enable gesture pass through so that both the parent and the child widget receive the gesture.

Allow-multiple-gestures.dart

import 'package:flutter/gestures.dart';
import 'package:flutter/material.dart';

//Main function. The entry point for your Flutter app.
void main() {
  runApp(
    MaterialApp(
      home: Scaffold(
        body: DemoApp(),
      ),
    ),
  );
}

//   Simple demo app which consists of two containers. The goal is to allow multiple gestures into the arena.
//  Everything is handled manually with the use of `RawGestureDetector` and a custom `GestureRecognizer`(It extends `TapGestureRecognizer`).
//  The custom GestureRecognizer, `AllowMultipleGestureRecognizer` is added to the gesture list and creates a `GestureRecognizerFactoryWithHandlers` of type `AllowMultipleGestureRecognizer`.
//  It creates a gesture recognizer factory with the given callbacks, in this case, an `onTap`.
//  It listens for an instance of `onTap` then prints text to the console when it is called. Note that the `RawGestureDetector` code is the same for both
//  containers. The only difference being the text that is printed(Used as a way to identify the widget) 

class DemoApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return RawGestureDetector(
      gestures: {
        AllowMultipleGestureRecognizer: GestureRecognizerFactoryWithHandlers<
            AllowMultipleGestureRecognizer>(
          () => AllowMultipleGestureRecognizer(),
          (AllowMultipleGestureRecognizer instance) {
            instance.onTap = () => print('Episode 4 is best! (parent container) ');
          },
        )
      },
      behavior: HitTestBehavior.opaque,
      //Parent Container
      child: Container(
        color: Colors.blueAccent,
        child: Center(
          //Wraps the second container in RawGestureDetector
          child: RawGestureDetector(
            gestures: {
              AllowMultipleGestureRecognizer:
                  GestureRecognizerFactoryWithHandlers<
                      AllowMultipleGestureRecognizer>(
                () => AllowMultipleGestureRecognizer(),  //constructor
                (AllowMultipleGestureRecognizer instance) {  //initializer
                  instance.onTap = () => print('Episode 8 is best! (nested container)');
                },
              )
            },
            //Creates the nested container within the first.
            child: Container(
               color: Colors.yellowAccent,
               width: 300.0,
               height: 400.0,
            ),
          ),
        ),
      ),
    );
  }
}

// Custom Gesture Recognizer.
// rejectGesture() is overridden. When a gesture is rejected, this is the function that is called. By default, it disposes of the
// Recognizer and runs clean up. However we modified it so that instead the Recognizer is disposed of, it is actually manually added.
// The result is instead you have one Recognizer winning the Arena, you have two. It is a win-win.
class AllowMultipleGestureRecognizer extends TapGestureRecognizer {
  @override
  void rejectGesture(int pointer) {
    acceptGesture(pointer);
  }
}

Hi @2p31-1 ,
To achieve what I wanted, I drilled down to use Flutter's lower level: Listener widget. As @TheManuz said, in this case it fires pretty well.
After struggling with this, I decided to make a talk about it to explain what I've understood from the subject. If you want to take a look, maybe that'll clarify some things for you:
https://www.droidcon.com/2023/08/06/understanding-flutters-handling-of-gestures/

Hii @Nash0x7E2m,

I've applied this solution for the session management and now I'm getting error like:

'package:flutter/src/gestures/tap.dart': Failed assertion: line 213 pos 14: '_down == null && _up == null': is not true.

This error happens, when I try to scroll the scrollable widgets and then after not able to detect the instance.onTap also.