Re: Copying preserves font-lock-face

[Richard Stallman]

`font-lock-face' is used by major modes that "manually" implement
fontification.  They set up `font-lock-face' properties.

Font Lock mode uses `char-property-alias-alist' to cause
`font-lock-face' properties to be displayed as if they were `face'
properties.

So I guess we need to get rid of `font-lock-face' properties when
yanking, at least usually.  However, in buffers where all faces are
assigned "manually", perhaps we should instead convert them to `face'
properties.