Re: add-face-text-property destructively modified properties

[Stefan Monnier]

> When I added add-face-text-property, it was for shr, which only uses it
> for buffers where this isn't a problem (I think...?),

I'm pretty sure the problem can occur in buffers as well.
E.g. if you (put-text-property X Y 'face '(a b c d)) at variable places
(hence using the exact same list object as `face` property at various
places) and then use add-face-text-property on some of those places.
[ both within a given buffer and between different buffers.  ]


        Stefan