Add some more clarifications on ui-* fonts

Author: NightFurySL2001

css-fonts-4/Overview.bs

@@ -597,7 +597,7 @@ Generic font families</h4>
 
 			The precise font(s) used will depend on factors such as 
             platform support, platform language, locale settings, 
-			user settings, Unicode coverage and the content language.
+			user preferences, Unicode coverage and the content language.
             UA may optionally choose to use the text rendering engine provided by the platform when using
             ''system-ui'' to match the appearance of the default user interface more closely.
 
@@ -744,6 +744,8 @@ Generic font families</h4>
 	        Note: ''ui-serif'' is not expected to map to any font on platforms
 	        without an appropriate system font.
 
+			Note: see notes on ''system-ui'' for potential issues.
+
 	        <div class="example" id="ex-sample-ui-serif">
 	            <figure>
 	                <img alt="sample ui-serif font" src="images/ui-serif.png" >
@@ -760,6 +762,8 @@ Generic font families</h4>
 	        Note: ''ui-sans-serif'' is not expected to map to any font on platforms
 	        without an appropriate system font.
 
+			Note: see notes on ''system-ui'' for potential issues.
+
 	        <div class="example" id="ex-sample-ui-sans">
 	            <figure>
 	                <img alt="sample ui-sans-serif font" src="images/ui-sans-serif.png" >
@@ -777,6 +781,8 @@ Generic font families</h4>
 	        Note: ''ui-monospace'' is not expected to map to any font on platforms
 	        without an appropriate system font.
 
+			Note: see notes on ''system-ui'' for potential issues.
+
 	        <div class="example" id="ex-sample-ui-mono">
 	            <figure>
 	                <img alt="sample ui-monospace font" src="images/ui-monospace.png" >
@@ -793,6 +799,8 @@ Generic font families</h4>
 	        Note: ''ui-rounded'' is not expected to map to any font on platforms
 	        without an appropriate system font.
 
+			Note: see notes on ''system-ui'' for potential issues.
+
 	        <div class="example" id="ex-sample-ui-rounded">
 	            <figure>
 	                <img alt="sample ui-rounded font" src="images/ui-rounded.png" >
@@ -8158,7 +8166,10 @@ Any Installed Font which is not a User-Installed font is a Preinstalled Font. It
 <h3 id="system-font">
 System Font</h3>
 
-The System Font is the font which is used by the ''system-ui'' <a href="#system-ui-def">generic font family name</a>. It is an example of a Preinstalled Font.
+The System Font is the font which is used by the ''system-ui'' <a href="#system-ui-def">generic font family name</a>. It is an example of a Preinstalled Font. 
+
+Additional font styles may also be provided as <a href="#ui-sans-serif-def">''ui-sans-serif''</a>, <a href="#ui-serif-def">''ui-serif''</a>, <a href="#ui-monospace-def">''ui-monospace''</a>, 
+and <a href="#ui-rounded-def">''ui-rounded''</a> which are also Preinstalled Font(s) if the system provides them.
 
 <wpt>
 	system-ui-ar.html