[bug] fullscreen viewer doesn't work from an iframe

[pilem]

First, thanks for making Filestash, it is an excellent tool. Great work.

Description of the bug

When Filestash is in an iframe, the viewer's fullscreen feature doesn't work.

Step by step instructions to reproduce the bug

Open Filestash in an iframe View a document : image, video, pdf, etc. Click the fullscreen icon

Can you replicate that error from the demo?

Yes, with this link : https://pilem.info/filestash-iframe.html It contains the demo in an iframe. Find or upload an image and test.

Observed behavior

Nothing happens.

Expected behavior

The document is viewed in fullscreen, like when filestash is not in an iframe.