Mount supports only IMG disk images, not JSON disk images

[harlev]

Trying to mount the content of https://diskettes.pcjs.org/pcx86/sys/dos/ibm/2.00/PCDOS200-DISK1.json, saved to a local file.
Clicking "choose file" and then "mount".
Always getting "FDC: Unrecognized disk format"

[jeffpar]

The mount feature is designed for "raw" disk images (ie, .IMG disk image files, not .JSON disk images). However, the mount feature could be more forgiving and either convert the JSON automatically or at least display a clearer error message.

[qodeos]

#68
Obviously now this issue is even worse, can’t load any file ext because there is no load file with choose file