I have a simple form with just a field to upload a file on a Drupal 8 site using the Webform module 6.0.1. If I test the form using webforms test tool, the file gets uploaded fine, it displays the loading icon for couple seconds and its ready to upload, but if I try the same in a page with the form embedded as a block, I can not upload the file it will always show me the following message if I try to submit the form, no matter how long I wait.

"File upload in progress. Uploaded file may be lost. Do you want to continue?"

Just for testing, I increased the max upload file to 2GB and the file I'm uploading is just 5kb. All the .js libraries I can think of are on my template.info.yml file. (core/drupal, core/jquery, core/drupal.ajax) The private folder has been set up in my settings.php and has the permissions set correctly the .htaccess file is also set as recommended for Drupal. I have try to upload the files in the public folder just as desperation but I get the same error

Any help will be appreciate.