Hybrid Drupal 8 with unhosted web apps or JavaFX Web Start apps?

I’m looking into using Drupal as the “back end (ish)” for a web site I want to build. In my research I have discovered the concept of “hybrid” Drupal, where you use Drupal to organize the site and for the navigation controls around a “frame” where you can then put regular web-based content. My question is: What can go in that frame? Can you put anything that would go on a normal, plain-vanilla web page? What about “unhosted web apps“? What about a JavaFX webstart app?

Basically, I want to create a web site with a collection of pages. Many of these pages will actually be web-based apps. I want each app to be able to run completely independently, even be able to be downloaded and run on the user’s machine, completely offline. For some of these apps, JavaFX would be more appropriate.

I do not, repeat do not, expect Drupal to enable or facilitate this offline usability. All I expect Drupal to do is stay out of the way. I want to use Drupal for the bulk of the site (wikis, comment sections, blogs, navigation, etcetera) because I don’t want to have to build all that back-end crap myself. But, for the pages where I need to use a JavaScript web app or a JavaFX Web Start app, I need Drupal to just present that app inside a frame and let that app do it’s own thing, just like any other web page. But, before I go to all the trouble to learn advanced Drupal, I would like to make sure there isn’t going to be a brick wall at the end of the rainbow.

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