Failing "multipart upload" to Cloudflare R2 for files > 5MB

I have read Error on uploading files bigger than 5MB Google Cloud Storage (GCS) S3 and this issue had been resolved:

Google Cloud bucket S3 interoperability interface does not support multipart-upload. WinSCP will not attempt that when connected to the Google Cloud

However for Cloudflare R2, uploads of files >5MB fail independent of "Enable transfer resume/transfer to temporary filename" (Preferences > Transfer > Endurance) settings.

The only program that uploads files >5MB to Cloudflare R2 without any issues that I know is Cyberduck but that program has lots of other issues including its interface.

Can that be fixed?

Thanks for your report.

I have added this issue to the tracker:
Issue 2237 – Multipart upload to Cloudflare R2 S3 interface fails due to too long upload ID

I'm sending you an email with a development version of WinSCP to the address you have used to register on this forum.

This version fixes it!

Thanks for your feedback!