[gimp-help] doc: replace Mac OS X with macOS in a few places.

[Jacob Boerema <jboerema src gnome org>]

commit 88ad59b382e877fd92d42a2f4107c785ee137d8e
Author: Jacob Boerema <jgboerema gmail com>
Date:   Thu Jun 24 16:49:10 2021 -0400

    doc: replace Mac OS X with macOS in a few places.

 src/concepts/intro.xml |  4 ++--
 src/introduction.xml   | 23 +++++++++++------------
 2 files changed, 13 insertions(+), 14 deletions(-)
---
diff --git a/src/concepts/intro.xml b/src/concepts/intro.xml
index 24ef991f8..c3eedd0bf 100644
--- a/src/concepts/intro.xml
+++ b/src/concepts/intro.xml
@@ -45,7 +45,7 @@
     </para>
     <para>
       <productname><acronym>GNU</acronym>/Linux</productname>,
-      <productname>Apple Mac OS X</productname>,
+      <productname>Apple macOS</productname>,
       <productname>Microsoft Windows</productname>,
       <productname>OpenBSD</productname>, <productname>NetBSD</productname>,
       <productname>FreeBSD</productname>, <productname>Solaris</productname>,
@@ -139,7 +139,7 @@ start gimp-2.10.exe</userinput></literallayout>
         </listitem>
       </varlistentry>
       <varlistentry>
-        <term>Under Apple Mac OS X</term>
+        <term>Under Apple macOS</term>
         <listitem>
           <para>
             From <guilabel>System Preferences</guilabel>, click the <guiicon>International</guiicon> icon. In
diff --git a/src/introduction.xml b/src/introduction.xml
index dfd8145c3..6ed8a369c 100644
--- a/src/introduction.xml
+++ b/src/introduction.xml
@@ -40,18 +40,17 @@
     image manipulation procedures to be easily scripted.
   </para>
   <para>
-    One of The <acronym>GIMP</acronym>'s strengths is its free
-    availability from many sources for many operating systems. Most
-    <acronym>GNU</acronym>/<application>Linux</application> distributions
-    include The <acronym>GIMP</acronym> as a standard application.
-    The <acronym>GIMP</acronym> is also available for other
-    operating systems such as <productname>Microsoft Windows</productname>
-    or Apple's <productname>Mac OS X</productname>
-    (<application>Darwin</application>). The <acronym>GIMP</acronym>
-    is a Free Software application covered by the General Public License
-    <xref linkend="bibliography-online-gpl"/>. The <acronym>GPL</acronym>
-    provides users with the freedom to access and alter the source code that
-    makes up computer programs.
+    One of <acronym>GIMP</acronym>'s strengths is its free availability from
+    many sources for many operating systems. Most <acronym>GNU</acronym> /
+    <application>Linux</application> distributions include
+    <acronym>GIMP</acronym> as a standard application.
+    <acronym>GIMP</acronym> is also available for other operating systems such
+    as <productname>Microsoft Windows</productname> or Apple's
+    <productname>macOS</productname> (<application>Darwin</application>).
+    <acronym>GIMP</acronym> is a Free Software application covered by the
+    General Public License version 3 <xref linkend="bibliography-online-gpl"/>.
+    The <acronym>GPL</acronym> provides users with the freedom to access and
+    alter the source code that makes up computer programs.
   </para>
 
   <sect2 id="authors">