Description of libwebp in gnuplot document (6.0 and 6.1)

[Tatsuro M. <tma...@ya...>]

Does the description of libwebp in any gnuplot documents?
I could nor find it in the INSTALL for 6.1 and 6.0.
To use the webp terminal, one has to install libwebp as dependencies for 6.0 and 6.1.

Tatsuro