This is a string for storing file name associated with BackgroundImage
property BackgroundImageFileName: TRVUnicodeString;
(introduced in v1.9; changed in version 18)
If rvsoUseItemImageFileNames is included in the Options parameter of SaveHTML/SaveHTMLEx, images with defined (non-empty) file names will not be saved, but their file names will be written in HTML (unlike pictures and tables, cells are not items, so this property cannot be accessed using item string properties).
See also properties of table: