Currently, the implementation of the PdfFormatProvider supports the import of Link and Widget annotations. However, other annotation types, such as Text and Pop-up annotations, are imported with limited support - only some of their visual appearance properties are imported. This leads to unpredictable results when exporting or merging. However, the exception could be avoided and the annotation can be skipped. This will ensure the client application is running without errors.

Currently, the unsupported Structured document tags (SDTs) in the document are skipped on import.

Implement support for content controls (a.k.a. Structured document tags), which will allow inserting editing controls in the document:

- Rich Text
- Plain Text
- Check Box
- Combo Box
- Drop-down list
- Date picker

Do not confuse this feature with form fields support (see https://feedback.telerik.com/Project/184/Feedback/Details/219850 ).