to the end of a very large buffer.
Beginning with version 21.3, a parenthesis or a brace in column zero
-is highlighted in bold-red face, to indicate that it could interfere
-with Font Lock and should be moved or escaped with a backslash.
+is highlighted in bold-red face if it is inside a string or a comment,
+to indicate that it could interfere with Font Lock (and also with
+indentation) and should be moved or escaped with a backslash.
If you don't use large buffers, or have a very fast machine which
makes the delays insignificant, you can avoid the incorrect