TypeError for attached json file

[tomceek]

Just attached JSON file to the page (via Page media) and got this error:

Fetch Failed: Cannot convert undefined or null to object TypeError: Cannot convert undefined or null to object at Function.keys () at http://www.xxx/user/plugins/admin/themes/grav/js/admin.min.js?3d05d80838:5:19999 at http://www.xxx/user/plugins/admin/themes/grav/js/admin.min.js?3d05d80838:4:24799 at

Grav v1.3.0-rc.5/Admin Panel v1.5.0-rc.4

Other file types woks fine.

Any help?

[flaviocopes]

Uhm.. I can't replicate this problem. Can you please go in the network panel of the browser dev tools, and after you upload the file check what is the response for the request?

[tomceek]

Upload is working fine. File sits in the folder, it generates thumbnail instantly after upload.
But when I open page for edit (refresh after uploading the file), I got that error mentioned above.

More info from Network panel:

[tomceek]

any update on bug fix?

[rhukster]

This is because of a missing JSON thumbnail in the Grav core.. Will be fixed in next release.