css prefix for presto engine

Question

According to Wikipedia prefix for presto is -XV-

-xv-color: #FF0;     /* paragraphs in yellow for Presto browsers */

I wanted to know for presto browser the prefix is -O- or -XV-. Is Wikipedia wrong??

Answer 1

In the Opera documentation about HTML and XHTML, we document the support of -xv-.

XHTML+Voice Profile (X+V)

Opera Presto fully supports the XHTML+Voice profile (and the Mobile Profile subset).

• The support of X+V includes support of CSS3 Speech (with an -xv- prefix as this module is under preparation).
• X+V needs to be served as an XML media type (application/xml, application/xhtml+xml, application/x-xhtml+voice+xml) for XML Events to take effect.
• For more information see the X+V developer documentation.

On Opera Web Developer documentation, you will find a few articles explaining xv extension.