Disable hyphenation and adjustment (local change).
Index: tmac/troffrc
--- tmac/troffrc.orig
+++ tmac/troffrc
@@ -41,10 +41,16 @@ troffrc!X100 troffrc!X100-12 troffrc!lj4 troff!lbp tro
 .\" Set the hyphenation language to 'us'.
 .do hla us
 .
-.\" Load hyphenation patterns and exceptions.
-.do hpf hyphen.us
-.do hpfa hyphenex.us
+.\" Disable hyphenation:
+.\" Do not load hyphenation patterns and exceptions.
+.\"do hpf hyphen.us
+.\"do hpfa hyphenex.us
 .
+.\" Disable adjustment by default,
+.\" such that manuals look similar with groff and mandoc(1).
+.ad l
+.de ad
+..
 .\" Handle paper formats.
 .do mso papersize.tmac
 .