solve 51% error installation of magento 2.4 & requirejs error when opening the admin panel

error 1:

 https://magento.stackexchange.com/questions/311806/installation-at-51-module-magento-theme-error-in-magento-2

solution:

private function validateURLScheme(string $filename) : bool
  {
      $allowed_schemes = ['ftp', 'ftps', 'http', 'https'];
      $url = parse_url($filename);
      if ($url && isset($url['scheme']) && !in_array($url['scheme'], $allowed_schemes) && !file_exists($filename)) {
          return false;
      }

      return true;
  }

error 2:

Refused to execute script from '<URL>' because its MIME type ('text/html') is not executable, and strict MIME type checking is enabled.

require.js:166 Uncaught Error: Script error for: mage/backend/bootstrap

require.js:166 Uncaught Error: Script error for: js/theme

require.js:166 Uncaught Error: Script error for: jquery

require.js:166 Uncaught Error: Script error for: mage/adminhtml/globals

require.js:166 Uncaught Error: Script error for: Magento_Catalog/catalog/product

solution: (kind  of)

I executed following steps:

Manually remove pub/static/frontend and pub/static/adminhtml
Run bin/magento setup:static-content:deploy in the Magento root directory
Run bin/magento cache:clean
even the above didn't work

error 3: 
Class Magento\Framework\View\Element\Template\File\Validator does not exist

when i added this code to line no. 139 (ref: video on youtube)
//$realPath = str_ireplace('\\', '/', $this->fileDriver->getRealPath($path);

location: magento\lib\internal\Magento\Framework\View\Element\Template\File
\Validator.php
( for new magento 2.4v)

you can find validator.php in magento\vendor\Magento\Framework\View\Element\Template
\File\Validator.php 
in old magento version

Final solution to get rid of all the requirejs and MIME type errors:

from this
if (0 === strpos($realPath, $directory)) {
    return true;
}
to this

if (0 === strpos($path, $directory)) {
     return true;
}