Site runs into error when new module permissions are set

The error also appears when I click on the "Manage Permissions" tab for any Content Type, including Basic Page

Start by reading Drupal’s logs, which is on the reports menu.

Thank you, @cilefen. Maybe the first time I have made use of Drupal reports !

What I found was rather weird. I'll explain and let me know if therein lies a bug.

I had deleted two custom fields from my Content Type. And that was the root cause. Drupal was trying to assign roles to those 'non-existent fields' ! How is this even possible? Since I am still in dev phase, deleted the nodes that were previously using those deleted fields. And then added back these two fields. That solved the problem.

Here's the error message:

RuntimeException: Adding non-existent permissions to a role is not allowed. The incorrect permissions are "view field_number_of_scans". in Drupal\user\Entity\Role->calculateDependencies() (line 207 of /home3/brandwa1/public_html/core/modules/user/src/Entity/Role.php).

I have never come across this situation, after deleting a field.

You could search the Internet for drupal "Adding non-existent permissions to a role is not allowed" as there have been prior reports. I don't know if there has been a definitive answer or whether this is caused by contributed modules with bugs.

Okay. Thank you.

As a layman, I can't comment on the tech part of it. Found that roles.yaml has got a piece explicitly to deal with this situation.

We keep deleting fields, but it doesn't throw up this error always. So, as you said, contrib modules may be bringing in this element....

I have tested this on local and it is working as expected, PHPUnit testing taking more time so here I am adding the code, Modified the Function to Automatically Handle Invalid Permissions

/**
   * {@inheritdoc}
   */
  public function calculateDependencies() {
    parent::calculateDependencies();
    // Load all permission definitions.
    $permission_definitions = \Drupal::service('user.permissions')->getPermissions();
    $valid_permissions = array_intersect($this->permissions, array_keys($permission_definitions));
    $invalid_permissions = array_diff($this->permissions, $valid_permissions);
    if (!empty($invalid_permissions)) {
      \Drupal::logger('user')->warning('Removing non-existent permissions from role: "@permissions".', ['@permissions' => implode(', ', $invalid_permissions)]);
      // Remove invalid permissions from the role.
      $this->permissions = $valid_permissions;
    }
    foreach ($valid_permissions as $permission) {
      // Depend on the module that is providing this permissions.
      $this->addDependency('module', $permission_definitions[$permission]['provider']);
      // Depend on any other dependencies defined by permissions granted to
      // this role.
      if (!empty($permission_definitions[$permission]['dependencies'])) {
        $this->addDependencies($permission_definitions[$permission]['dependencies']);
      }
    }
    return $this;
  }

Logging Instead of Throwing an Exception:
Instead of throwing a RuntimeException, we log a warning using \Drupal::logger('user')->warning() when invalid permissions are found. This allows the system to recover from the error without breaking.

Automatically Removing Invalid Permissions:
The invalid permissions are removed from the role by resetting $this->permissions to $valid_permissions. This ensures that roles are no longer linked to non-existent permissions.

Rest of the Logic Remains Unchanged:
The valid permissions are processed as they were originally, adding necessary dependencies based on the permissions.