Steps to reproduce the issue

1. Open any PDF form document in Adobe Acrobat (web version or desktop app).
2. Select Fill & Sign tool.
3. Add text in Cyrillic Serbian (e.g., „Петар Петровић“, „Београд“, etc.).
4. Save the document.
5. Reopen the saved PDF.

Environment (OS, versions, etc.)

Device: MacBook (Apple Silicon M1)
Operating System: macOS, latest available on M1
Adobe Product: Adobe Acrobat Web (browser-based Fill & Sign), Adobe Acrobat Desktop Application (installed version)
Issue does not appear when editing on non-Mac environments (tried on Windows 11 PC).
Problem occurs consistently in both browser and installed Acrobat app on MacBook M1.

Expected result

Text entered in Cyrillic using Fill & Sign should be properly saved and visible when the PDF is reopened.
All characters, including Serbian Cyrillic letters, should remain intact.

Observed result

After saving and reopening the document, all Cyrillic text entered via Fill & Sign disappears or is not displayed.
Only non-Cyrillic elements remain visible, such as:
- Numbers
- Checked boxes
- Other non-Cyrillic characters

This makes the saved form incomplete and unusable for Serbian-language documents.