attachEvent (“onBeforeDelete”) on .files.data is not enough.
When return false to the event, to keep the file, File with status “server” remains in the list, but its status is changed on “client”. It’s a bug.
Hello,
I can confirm the incorrect behaviour. It is caused by the inner onBeforeDelete handler that aborts uploading (if it is active) for the files that are about to be deleted.
We will include the fix in the next release.