Photoshop 2026 (27.8.0) Generator: hidden hard limit of 10k width for output?

Photoshop version: 27.8.0
OS: macOS 13.7.5
Hardware: MacBook Pro 2019 / 32 GB RAM / 8GB AMD GPU

Steps to reproduce:

1. Create a new Photoshop document: 12000 × 6000 px
2. Add a full-canvas layer/group
3. Enable File → Generate → Image Assets
4. Name layer:
   test.png

Result:
Generated image output is 9999 × 4999 px instead of 12000 × 6000 px.

Additional tests:

* Explicit naming:

  * test.png,12000x6000
  * test.png,15000x7500
  * test.png,16000x8000
* PNG and JPEG tested
* Deleted generated assets folder
* Restarted Photoshop
* Fresh PSD created
* Same result every time

Observed behavior:
Generate Image Assets appears to clamp the exported image to approximately 10,000 px maximum dimension and proportionally rescales the image, sometimes producing 9999 px instead of 10000 px.

Expected behavior:
Generated asset should match requested dimensions or source dimensions.