Pages that have background pages that in turn have background pages don't show the lowest level background page

[GregKGS]

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Describe the bug Pages that have background pages (that in turn have background pages) do not show the entire "stack" of background pages, only the first background page.

To Reproduce Steps to reproduce the behavior:

1. Create three pages. Add shapes to each page
2. Set page 2 to have background = page 3
3. Set page 1 to have background = page 2

Expected behavior All shapes should be visible on page 1

Actual behavior Only shapes from page 1 and 2 are visible.

Screenshots If applicable, add screenshots to help explain your problem.

draw.io version (In the Help->About menu of the draw.io editor):

• draw.io version 26.2.15

Desktop (please complete the following information):

• OS: Win 11
• Browser: Electron?
• Browser Version

I tested the problem in incognito/private mode with all browser extensions switched off, write "yes" below: Not applicable (desktop app)