Description:
I keep running into issues when creating accessible PDFs from Impress, specifically with what seems to be an incorrectly tagged background. 

Regardless of whether the background is a solid color or an image, the result is always the error: “Untagged path object” or “Untagged image object.” If the background in the master slides is set to “None,” this problem doesn’t occur. 

Steps to Reproduce:
1. Create a presentation with 4 slides and 4 master slides:
- Slide 1: no background
- Slide 2: white background with black text
- Slide 3: black background with white text
- Slide 4: graphic as background, no text
2. Export the presentation as PDF/A-3b (1.7).
- Universal Accessibility (PDF/UA): enabled
- Tagged PDF: enabled
- Export outline: enabled (but grayed out because of PDF/UA)
3. Validate the exported PDF with PAC (https://pac.pdf-accessibility.org/en or check.axes4.com 

Actual Results:
After creating the PDF and checking it with PAC, I got the error described above on 3 of the 4 slides.
On slides with backgrounds (solid color or image), PAC reports:
- “Untagged path object” (solid color background)
- “Untagged image object” (graphic background)
Only the slide with no background passes without errors.

Expected Results:
Im not quite familiar with the PDF/UA-Standard, I think the background should be tagged as an artifact (Background).


Reproducible: Always


User Profile Reset: No

Additional Info:
"139007"