RE: Overlay before-string property

["Drew Adams" <drew.adams@oracle.com>]

    > Unfortunately, the depth-indicator overlay picks up the face
    > used for the first character of the prompt string. I don't
    > want that - I want it to have its own face (e.g. the default).
    > So, I tried adding this at the end of the above code:
    >     (overlay-put minibuf-depth-overlay 'face 'default)

    Put the face property on the before-string string.

OK, that makes sense (and it works). Thanks.

However, I'd like to be able to just use the existing code as is, without
redefining it. That is, I'd prefer to do something simple after loading the
file minibuf-depth.el, rather than rewriting part of it.

Can you explain what is going on here, so I can understand it? Is this a
quality of the `before-string' property, in general, or does it result from
something else?

And should Miles' code (presumably to be added to Emacs after the release)
not result in this stickiness, or is it intended (does it have some
benefit)?