diff --git a/doc/sandbox.mdwn b/doc/sandbox.mdwn
index 002b4f3bf..d0cc29ab7 100644
--- a/doc/sandbox.mdwn
+++ b/doc/sandbox.mdwn
@@ -4,6 +4,9 @@ This is the SandBox, a page anyone can edit to try out ikiwiki.
 
 So, I'm wondering why ikiwiki requires links to have no spaces in their names, and uses .html suffixes. I really don't like having to use [[CamelCase]] for multi-word links, and it's generally not good practice to encode stuff like filetype or specific technologies in the URL; that's what we have a MIME type for. Anyhow, this is really just a test for playing around in the sanbox, but those are the two things that bother me the most off the bat about ikiwiki.
 
+> For the former: because links with spaces get parsed as [[preprocessor_directives|preprocessordirectives]].  You can get away with it if the first word doesn't correspond to a preprocessor directive.  If you have another syntax you'd prefer, feel free to propose it.  For instance, I can imagine extending the syntax with something like [["link with spaces"]].
+> For the latter: see the new `usedirs` option if you want to avoid .html suffixes.
+
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 testing openid ... ignore.