Module development and code questions

Hi everyone!

I'm creating a module in Drupal 7 for ticket booking and I need a little help.

I have added a menu link where my newly created module opens up a form and that form needs to have: 

a hidden field for current user

a field with performance title for users to choose from

a field with dates available (this should actually be nested within the performance, but first things first)

a filed with number of tickets that user wants to purchase

In a hook for alter, I try to set a default image, that is the user posted picture.

$author = $node->getOwner();

$user = \Drupal\user\Entity\User::load($author->id());

if (!$user->user_picture->isEmpty()) {

   $displayImg = file_create_url($user->user_picture->entity->getFileUri());

   $form['field_avatar']['widget'][0]['#default_image'] = $displayImg;

I'm using this version of brightcove in D9

"drupal/brightcove": "dev-3146320-D9-compatibility",

and this error showed up when I clicked on edit button.

I'm using module "Commerce Ajax Add to Cart" create button Add to Cart on Detail Product. But when I click "Add to Cart", It got a error 
"[Deprecation] Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user's experience. For more help, check https://xhr.spec.whatwg.org/"
 This is a link error.

hello,

i've has installation module google analytics in my server and localhost. but i've already follow step in this linka https://www.youtube.com/watch?v=EOr8A68koEg to do, the module is still not working and tracking id.

Why is not working?

having any solution for this?

 I'm a new Drupal developer and this is my first time writing test for an existing module created by another developer. I am using the WebDriverTestBase with chromedriver. When running the test, the main page does load out in the chromedriver browser. However, when the code below runs, it says Page Not Found.