Invalid backend response since 12.3

[olia-bn]

Describe the bug Upgrading from 12.2.3 to ^12.3 (currently 12.3 and 12.3.1) causes "Invalid backend response" when accessing the connector.

To Reproduce Config is pretty stock, PHP 8.1.12 but happens on 8.2 as well.

fm_elfinder:
    instances:
        default:
            editor: form
            connector:
                roots:
                    uploads:
                        driver: LocalFileSystem
                        path: uploads

(OPTIONAL) Additional context Other people reported the issue in the last 2 weeks but closed it after finding the workaround: enabling CORS support makes the problem dissapear.

But that's a workaround, not a fix (and potential security risk): I am accessing the connector URL from the same domain on the client side.

[olia-bn]

Seems to me that the primary candidate for causing the issue is this commit

The behaviour change then affects the load function - and as expected, only if NOT in CORS mode.

[helios-ag]

hi @olia-bn, so lets revert it :)

[bobvandevijver]

12.3.2 does indeed fix this issue.

[olia-bn]

Indeed it's fixed