Microsoft

cftag (4 bytes): An unsigned integer specifying the clipboard format of the data. MUST be 0x00000000, CF_WINDOWS (0xFFFFFFFF), or CF_MACINTOSH (0xFFFFFFFE). A value of 0x00000000 specifies that there is no image data associated with the property. formatId (4 bytes): An unsigned integer specifying the format of the data stored in the cfDataBytes ... ................
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