Font embedding has been possible with Portable Document Format (PDF), Microsoft Word for Windows and some other applications for many years.
[4][5] For example, if a .rtf file made in Microsoft Word is opened in LibreOffice Writer, it will usually remove the embedded fonts.
[citation needed] Browsers Internet Explorer, Firefox, Safari, Opera and Google Chrome support automatic downloading of fonts used on a website using CSS2 or CSS3.
This reduces file size but prohibits adding previously unused characters to the document.
Because of the potential for copyright infringement, Microsoft Internet Explorer only permits embedded fonts that include digital rights management (DRM) protections.