When a form is blocked on a page, the message We had some trouble loading this form. Click here to continue. will appear in place of the form.
The Click here to continue text is hyperlinked to https://f.hsforms.net, a protected domain controlled by HubSpot. When a visitor clicks the link, they'll be brought to a standalone form page where they can submit the form.
The link includes the full context of the original form's embed code in a query string, as well as the original page information like its title and URL. As a result, the form on this standalone page will behave exactly like the original form, and a form submission on this standalone page will pass the same analytics information as a submission on your original form.