Downloadable files are corrupt

[davelab6]

When I download a font from http://byte-foundry.github.io/plumin.js/interpolate.html it won't open in FontForge:

And ots says,

$ ot-sanitise ~/Downloads/demo.otf 
invalid version tag
Failed to sanitise file!
$

[louisremi]

When I click on Download in Firefox, I get one file with a random name and no .otf extension. It opens correctly in FontForge.
When I do the same in Chrome, I get two files: one named demo.otf which is corrupt, and one named download, with no .otf extension which opens correctly in FontForge.

I need to investigate this, but I suspect this is a problem with the code of the demo itself.

[davelab6]

Aha, I missed that download file!! :) cool!