Docs: add note re ordering engravers

diff --git a/Documentation/user/changing-defaults.itely b/Documentation/user/changing-defaults.itely
index 7f22418ebd7daccf7ba096fe2a67423a2f1077a4..4151c983370bf2c4bbd9ded7ff113295224a39d8 100644 (file)
--- a/Documentation/user/changing-defaults.itely
+++ b/Documentation/user/changing-defaults.itely
@@ -533,6 +533,21 @@ time signature.
 >>
 @end lilypond
 
+@knownissues
+
+Usually the order in which the engravers are specified
+does not matter, but in a few special cases the order
+is important, for example where one engraver writes
+a property and another reads it, or where one engraver
+creates a grob and another must process it.  The order in
+which the engravers are specified is the order in which
+they are called to carry out their processing.
+
+The following orderings are important: the
+@code{Bar_engraver} must normally be first, and
+the @code{New_fingering_engraver} must come before
+the @code{Script_column_engraver}.  There may be others
+with ordering dependencies.
 
 @node Changing context default settings
 @subsection Changing context default settings