Duplicate form id #blueprints on the same page in the admin panel

[TomOne]

In the admin panel there are sometimes multiple forms with the same id #blueprints on the same page, which is not allowed by the HTML standard. For example, there are 4 forms with the same #blueprints id on editing pages, e.g. /admin/pages/home. This can lead to problems, especially with JavaScript.

For instance it causes the language switcher in MS Edge (fixed in my pull request #1213) to break randomly because the form attribute polyfill uses id selectors for forms in JavaScript.

I’ve noticed that the Twig partials for the forms support a form_id variable, so it should be enough to just pass unique ids to form_id when including the partials, right?

[rhukster]

Yes, that's basically the solution. I've fixed the pages.html.twig to ensure that the modals each use a custom form_id. If you find any more please let me know or fix them yourself in a PR and i'll merge it. Cheers.