PHP Warning: count(): Parameter must be an array …

Hello!

Since a few days we are having php warnings created by your tool.

The entry in error_log is:
[29-Apr-2020 15:30:45 UTC] PHP Warning: count(): Parameter must be an array or an object that implements Countable in /home/kd63270/public_html/wp-content/plugins/drag-and-drop-multiple-file-upload-contact-form-7/inc/dnd-upload-cf7.php on line 411

The warnings started on 18th April. I updated the tool recently a few times, maybe on 18th, too. So maybe an update caused the warning?

The warnings are generated for every upload. We have a forms with two upload fieds, therefore there are two warning messages.

Tool Settings: Send attachment as link: YES
Other than that we only changed the labels for the upload fields. All other settings are set to default.

D&D field settings:
Field 1: PDF, max-file: 1, required
Field 2: PDF|mov|mp4, max-file: 1, required, file-size: 200mb (as bytes)

Additionally we use Advanced CF7 Database and Conditional Fields.

Good to know: Both the upload and email sending works! But it still would be great if we could find the reason for those warnings.

I appreciate any help!

Best regards