Photoshop 27.4.0 – PSD files in 16‑bit no longer generate thumbnails in Windows 11

Hello,

I am experiencing a reproducible issue with Photoshop 27.4.0 regarding PSD thumbnails in Windows 11.

Issue

Since updating to Photoshop 27.4.0, PSD files saved in 16‑bit no longer display a thumbnail in Windows File Explorer. Only 8‑bit PSD files generate a correct thumbnail.

Tests performed

• New A4 document with a solid background + text + drop shadow:

  • 8‑bit → thumbnail OK

  • 16‑bit → no thumbnail

• Older PSD files created with Photoshop 2026 (27.3.x):

  • Thumbnail is visible

  • As soon as I modify and save the file in 27.4.0 → thumbnail disappears

• The issue does not depend on:

  • file size

  • DPI

  • document dimensions

  • file weight (tested up to 140 MB)

The problem occurs only when the document is in 16‑bit mode.

Expected behavior

Previous versions of Photoshop (2026 / 27.3.x) correctly generated a Windows‑compatible thumbnail even for 16‑bit PSD files.

Conclusion

Photoshop 27.4.0 appears to no longer embed a Windows‑readable thumbnail in 16‑bit PSD files, which prevents Windows 11 (and third‑party thumbnail readers such as Pictus/Icaros) from displaying a preview.

Request

Could you please confirm whether this is:

• an intentional change in the way Photoshop handles thumbnails for 16‑bit documents, or

• an unintended regression introduced in version 27.4.0?

Thank you.