-# Treat this URL as an image. This only matters if it's also blocked, in
-# which case a "blocked" image rather than a HTML page will be sent.
-# (According to the tinygif setting in the config file).
+# Treat this URL as an image. This only matters if it's also "+block"ed,
+# in which case a "blocked" image can be sent rather than a HTML page.
+# See +image-blocker{} for the control over what is actually sent.
+#
+# +image-blocker{logo}
+# +image-blocker{blank}
+# +image-blocker{http://i.j.b/ijb-send-banner}
+# Decides what to do with URLs that end up tagged with {+block +image}.
+# There are 4 options. "-image-blocker" will send a HTML "blocked" page,
+# usually resulting in a "broken image" icon. "+image-blocker{logo}"
+# will send a "JunkBuster" image. "+image-blocker{blank}" will send
+# a 1x1 transparent GIF. And finally, "+image-blocker{http://xyz.com}"
+# will send a HTTP temporary redirect to the specified image - this
+# has the advantage of the icon being beeing cached by the browser,
+# which will speed up the display.