SUMMARY
In the archive extraction dialog, by default when it shows the filename field is empty and the "extract" button is disabled. The filename field is optional in the code, the "extract" button should be enabled even if this field is empty.

STEPS TO REPRODUCE
1. Open any archive with Ark.
2. Click on the "Extract" button to open the extraction dialog.

OBSERVED RESULT
The "extract" button to confirm the action is greyed-out (disabled), because the filename field is empty.

EXPECTED RESULT
The "extract" button should be enabled / clickable even if the filename field is empty, because it's optional (i.e. even if you write anything the extraction still works).

SOFTWARE/OS VERSIONS
KDE Plasma Version: 6.4.2
KDE Frameworks Version: 6.16.0
Qt Version: 6.8.2

ADDITIONAL INFORMATION
The code responsible for enabling/disabling the accept button is in KIO, right here:
https://invent.kde.org/frameworks/kio/-/blob/master/src/filewidgets/kfilewidget.cpp?ref_type=heads#L1318