virtualbox – What has changed in Windows 10 in the last month that could cause Zone.Identifier files to be created?

I run Windows 10 in a Virtualbox VM for the sole purpose of using a scanning application. At some point in the last month, something changed which means the scanned files now have accompanying Zone.Identifier files.

I know what these files are thanks to this question (they are alternate data streams), and I guess they are being created because the folder in question is a Virtualbox shared folder backed by a non-NTFS filesystem. What I cannot explain is why these files are being created now, but weren’t the last time I used the scanner (nor ever before in the nearly 10 years that I’ve been using this VM for this purpose).

The contents of the files are:

[ZoneTransfer]
ZoneId=3

which, for what it’s worth, seems to be incorrect, as according to this document zone 3 is the internet zone, but these files were created locally.

Aside from scanning, the only other thing this VM does is run Windows Update. Did something change in a recent update that has caused these files to start being created?