not widely supported either. Annotations Since RTF 1.0, the RTF specification has supported document annotations/comments. The RTF 1.7 specification defined some new features for annotations, including the date stamp (there was previously only "time stamp") and parents of annotations. When a RTF document with annotations is opened in an application that does not support RTF annotations, the annotations are not shown. Similarly, when a document with annotations is saved as RTF in an application that does not support RTF annotations, the annotations are not preserved in the RTF file. Some implementations, like Abiword (since version 2.8) and IBM Lotus Symphony (up to version 1.3), may hide annotations by default or require some user action to display them. The RTF specification also supports footnotes, which are widely supported in RTF implementations (e.g. in OpenOffice.org, Abiword, KWord, Ted, but not in Wordpad). Endnotes are implemented as a variation on footnotes, so applications that support footnotes but not endnotes will render an endnote as a footnote. Microsoft products do not support comments within footers, footnotes or headers. Similarly, Microsoft products do not support footnotes in headers, footers, or comments. Inserting a comment or a footnote in one of these disallowed contexts may result in a corrupted document. Drawing objects The RTF 1.2 specification defined use of drawing objects, known as shapes, such as rectangles, ellipses, lines, arrows and polygons. The RTF 1.5 specification introduced many new control words for drawing objects. However, many RTF implementations, such as Apache OpenOffice, do not support drawing objects (though they are supported in LibreOffice 4.0 on) or Abiword. Applications which do not support RTF drawing objects do not display or save the shapes. Some implementations will also not display any text inside drawing objects. Security concerns Unlike Microsoft Word's DOC format, as well as the newer Office Open XML and OpenDocument formats, RTF does not support macros. For this reason, RTF was often recommended over those formats when the spread of computer viruses through macros was a concern. However, having the .RTF extension does not guarantee a safe file, since Microsoft Word will open standard DOC files renamed with an RTF extension and run any contained macros as usual. Manual examination of a file in a plain text editor such as Notepad, or use of the file command in a UNIX-like systems, is required to determine whether or not a suspect file is really RTF. Enabling Word's