-.It \&.Dd Ta \&No Ta \&No Ta >0
-.It \&.Dt Ta \&No Ta \&No Ta n
-.It \&.Os Ta \&No Ta \&No Ta n
-.It \&.Pp Ta \&No Ta \&No Ta 0
-.It \&.Ad Ta Yes Ta Yes Ta n
-.It \&.An Ta \&No Ta Yes Ta n
-.It \&.Ar Ta Yes Ta Yes Ta n
-.It \&.Cd Ta Yes Ta \&No Ta >0
-.It \&.Cm Ta Yes Ta Yes Ta n
-.It \&.Dv Ta Yes Ta Yes Ta >0
-.It \&.Er Ta Yes Ta Yes Ta >0
-.It \&.Ev Ta Yes Ta Yes Ta >0
-.It \&.Ex Ta \&No Ta \&No Ta 0
-.It \&.Fa Ta Yes Ta Yes Ta >0
-.It \&.Fd Ta \&No Ta \&No Ta >0
-.It \&.Fl Ta Yes Ta Yes Ta n
-.It \&.Fn Ta Yes Ta Yes Ta >0
-.It \&.Ft Ta \&No Ta Yes Ta n
-.It \&.Ic Ta Yes Ta Yes Ta >0
-.It \&.In Ta \&No Ta \&No Ta n
-.It \&.Li Ta Yes Ta Yes Ta >0
-.It \&.Nd Ta \&No Ta \&No Ta n
-.It \&.Nm Ta Yes Ta Yes Ta n
-.It \&.Ot Ta \&No Ta \&No Ta n
-.It \&.Pa Ta Yes Ta Yes Ta n
-.It \&.Rv Ta \&No Ta \&No Ta 0
-.It \&.St Ta \&No Ta Yes Ta 1
-.It \&.Va Ta Yes Ta Yes Ta >0
-.It \&.Vt Ta Yes Ta Yes Ta >0
-.It \&.Xr Ta Yes Ta Yes Ta >0, <3
-.It \&.%A Ta \&No Ta \&No Ta >0
-.It \&.%B Ta \&No Ta \&No Ta >0
-.It \&.%C Ta \&No Ta \&No Ta >0
-.It \&.%D Ta \&No Ta \&No Ta >0
-.It \&.%I Ta \&No Ta \&No Ta >0
-.It \&.%J Ta \&No Ta \&No Ta >0
-.It \&.%N Ta \&No Ta \&No Ta >0
-.It \&.%O Ta \&No Ta \&No Ta >0
-.It \&.%P Ta \&No Ta \&No Ta >0
-.It \&.%R Ta \&No Ta \&No Ta >0
-.It \&.%T Ta \&No Ta \&No Ta >0
-.It \&.%V Ta \&No Ta \&No Ta >0
-.It \&.At Ta Yes Ta Yes Ta 1
-.It \&.Bsx Ta Yes Ta Yes Ta n
-.It \&.Bx Ta Yes Ta Yes Ta n
-.It \&.Db Ta \&No Ta \&No Ta 1
-.It \&.Em Ta Yes Ta Yes Ta >0
-.It \&.Fx Ta Yes Ta Yes Ta n
-.It \&.Ms Ta \&No Ta Yes Ta >0
-.It \&.No Ta Yes Ta Yes Ta 0
-.It \&.Ns Ta Yes Ta Yes Ta 0
-.It \&.Nx Ta Yes Ta Yes Ta n
-.It \&.Ox Ta Yes Ta Yes Ta n
-.It \&.Pf Ta \&No Ta Yes Ta 1
-.It \&.Sm Ta \&No Ta \&No Ta 1
-.It \&.Sx Ta Yes Ta Yes Ta >0
-.It \&.Sy Ta Yes Ta Yes Ta >0
-.It \&.Tn Ta Yes Ta Yes Ta >0
-.It \&.Ux Ta Yes Ta Yes Ta n
-.It \&.Bt Ta \&No Ta \&No Ta 0
-.It \&.Hf Ta \&No Ta \&No Ta n
-.It \&.Fr Ta \&No Ta \&No Ta n
-.It \&.Ud Ta \&No Ta \&No Ta 0
-.It \&.Lb Ta \&No Ta \&No Ta 1
-.It \&.Ap Ta Yes Ta Yes Ta 0
-.It \&.Lp Ta \&No Ta \&No Ta 0
-.It \&.Lk Ta \&No Ta Yes Ta >0
-.It \&.Mt Ta \&No Ta Yes Ta >0
+.It \&%A Ta \&No Ta \&No Ta >0
+.It \&%B Ta \&No Ta \&No Ta >0
+.It \&%C Ta \&No Ta \&No Ta >0
+.It \&%D Ta \&No Ta \&No Ta >0
+.It \&%I Ta \&No Ta \&No Ta >0
+.It \&%J Ta \&No Ta \&No Ta >0
+.It \&%N Ta \&No Ta \&No Ta >0
+.It \&%O Ta \&No Ta \&No Ta >0
+.It \&%P Ta \&No Ta \&No Ta >0
+.It \&%R Ta \&No Ta \&No Ta >0
+.It \&%T Ta \&No Ta \&No Ta >0
+.It \&%V Ta \&No Ta \&No Ta >0
+.It \&Ad Ta Yes Ta Yes Ta n
+.It \&An Ta Yes Ta Yes Ta n
+.It \&Ap Ta Yes Ta Yes Ta 0
+.It \&Ar Ta Yes Ta Yes Ta n
+.It \&At Ta Yes Ta Yes Ta 1
+.It \&Bsx Ta Yes Ta Yes Ta n
+.It \&Bt Ta \&No Ta \&No Ta 0
+.It \&Bx Ta Yes Ta Yes Ta n
+.It \&Cd Ta Yes Ta \&No Ta >0
+.It \&Cm Ta Yes Ta Yes Ta n
+.It \&Db Ta \&No Ta \&No Ta 1
+.It \&Dd Ta \&No Ta \&No Ta >0
+.It \&Dt Ta \&No Ta \&No Ta n
+.It \&Dv Ta Yes Ta Yes Ta n
+.It \&Dx Ta Yes Ta Yes Ta n
+.It \&Em Ta Yes Ta Yes Ta >0
+.It \&En Ta \&No Ta \&No Ta 0
+.It \&Er Ta Yes Ta Yes Ta >0
+.It \&Es Ta \&No Ta \&No Ta 0
+.It \&Ev Ta Yes Ta Yes Ta n
+.It \&Ex Ta \&No Ta \&No Ta 0
+.It \&Fa Ta Yes Ta Yes Ta n
+.It \&Fd Ta \&No Ta \&No Ta >0
+.It \&Fl Ta Yes Ta Yes Ta n
+.It \&Fn Ta Yes Ta Yes Ta >0
+.It \&Fr Ta \&No Ta \&No Ta n
+.It \&Ft Ta Yes Ta Yes Ta n
+.It \&Fx Ta Yes Ta Yes Ta n
+.It \&Hf Ta \&No Ta \&No Ta n
+.It \&Ic Ta Yes Ta Yes Ta >0
+.It \&In Ta \&No Ta \&No Ta n
+.It \&Lb Ta \&No Ta \&No Ta 1
+.It \&Li Ta Yes Ta Yes Ta n
+.It \&Lk Ta Yes Ta Yes Ta n
+.It \&Lp Ta \&No Ta \&No Ta 0
+.It \&Ms Ta Yes Ta Yes Ta >0
+.It \&Mt Ta Yes Ta Yes Ta >0
+.It \&Nm Ta Yes Ta Yes Ta n
+.It \&No Ta Yes Ta Yes Ta 0
+.It \&Ns Ta Yes Ta Yes Ta 0
+.It \&Nx Ta Yes Ta Yes Ta n
+.It \&Os Ta \&No Ta \&No Ta n
+.It \&Ot Ta \&No Ta \&No Ta n
+.It \&Ox Ta Yes Ta Yes Ta n
+.It \&Pa Ta Yes Ta Yes Ta n
+.It \&Pf Ta \&No Ta Yes Ta 1
+.It \&Pp Ta \&No Ta \&No Ta 0
+.It \&Rv Ta \&No Ta \&No Ta 0
+.It \&Sm Ta \&No Ta \&No Ta 1
+.It \&St Ta \&No Ta Yes Ta 1
+.It \&Sx Ta Yes Ta Yes Ta >0
+.It \&Sy Ta Yes Ta Yes Ta >0
+.It \&Tn Ta Yes Ta Yes Ta >0
+.It \&Ud Ta \&No Ta \&No Ta 0
+.It \&Ux Ta Yes Ta Yes Ta n
+.It \&Va Ta Yes Ta Yes Ta n
+.It \&Vt Ta Yes Ta Yes Ta >0
+.It \&Xr Ta Yes Ta Yes Ta >0, <3
+.It \&br Ta \&No Ta \&No Ta 0
+.El
+.\" SECTION---------------------------------------------
+.Sh COMPATIBILITY
+This section documents compatibility with other roff implementations, at
+this time limited to
+.Xr groff 1 .
+The term
+.Qq historic groff
+refers to those versions before the
+.Pa doc.tmac
+file re-write
+.Pq somewhere between 1.15 and 1.19 .
+.\" PARAGRAPH------------
+.Pp
+.Bl -dash -compact
+.\" LIST-ITEM
+.It
+Some character sequences in groff are not handled depending on escape
+style, e.g.,
+.Sq \e(ba
+and
+.Sq \e*(Ba
+may not be interchanged. This is no longer the case: all character
+sequences resolve to the same symbol, regardless the escape style.
+.\" LIST-ITEM
+.It
+Blocks of whitespace are stripped from both macro and free-form text
+lines (except when in literal mode), while groff would retain whitespace
+in free-form text lines.
+.\" LIST-ITEM
+.It
+Historic groff has many un-callable macros. Most of these (excluding
+some block-level macros) are now callable, conforming to the
+non-historic groff version.
+.\" LIST-ITEM
+.It
+The vertical bar
+.Sq \(ba
+made historic groff
+.Qq go orbital
+but is a proper delimiter in this implementation.
+.\" LIST-ITEM
+.It
+.Sq \&.It \-nested
+is assumed for all lists (it wasn't in historic groff): any list may be
+nested and
+.Sq \-enum
+lists will restart the sequence only for the sub-list.
+.\" LIST-ITEM
+.It
+.Sq \&.It \-column
+syntax where column widths may be preceded by other arguments (instead
+of proceeded) is not supported.
+.\" LIST-ITEM
+.It
+The
+.Sq \&.At
+macro only accepts a single parameter.
+.\" LIST-ITEM
+.It
+Some manuals use
+.Sq \&.Li
+incorrectly by following it with a reserved character and expecting the
+delimiter to render. This is not supported.
+.\" LIST-ITEM
+.It
+If an special-character control character is escaped
+.Sq \e\e ,
+it will obviously not render the subsequent sequence. Even newer
+versions of groff seem to dither on this.
+.\" LIST-ITEM
+.It
+In groff, the
+.Sq \&.Fo
+macro only produces the first parameter. This is no longer the case.