On iPad (iPad Air M3, latest iPadOS, 26.2), while you can view a PDF with the inbuilt viewer, you can't actually open one in the native viewer, or any external application - when using the "Open with" menu item it shows "No installed application can open these files". Even though iOS supports PDFs natively, and I've installed several apps that will handle them. As far as I can see there's no way to access the file outside of S3Drive itself - the (marked experimental) Enable Mount always defaults to off even if you enable it, the Files app shows an empty drive when you try it, and without being able to open with another app all that's left is the inbuilt preview - you can't save to files or anything else.
Testing with some other file types (mp4, png etc) the same occurs. This is using an encrypted Wasabi (S3) bucket, Ultimate enabled via login. The inbuilt preview works well enough, but obviously doesn't cover a whole bunch of things. So it seems to be a more general problem...
Oddly, on the app on iPhone, this seems to work - it opens the standard 'share' menu, and while you can't select the inbuilt viewer you CAN select 'Save to Files' or an app from the list.
This is kind of stopping my main use case - any help is appreciated! (edited)
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