1) In the Java Editor, turn on Show Line Numbers
2) Goto Windows Display Properties (right-click over empty area on desktop)
3) Select Appearance tab
4) Change Color Scheme ex. from Default (Blue) to Silver
5) Observe that Line Number column in Java Editor is now blank
6) Need to cycle IDE to have Line Numbers appear again.

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>Log Session: Tuesday, April 1, 2008 10:09:49 PM PDT
>System Info: 
  Product Version         = NetBeans IDE Dev (Build 200803191206)
  Operating System        = Windows XP version 5.1 running on x86
  Java; VM; Vendor        = 1.5.0_13; Java HotSpot(TM) Client VM 1.5.0_13-b05; Sun Microsystems Inc.
  Runtime                 = Java(TM) 2 Runtime Environment, Standard Edition 1.5.0_13-b05
  Java Home               = C:\HawaiiMAIN\build-tools\jdk1.5.0_13\jre
  System Locale; Encoding = en_US (nb); Cp1252
  Home Directory          = C:\Documents and Settings\edwong
  Current Directory       = C:\NB6\20080319-1205\bin
  User Directory          = C:\Documents and Settings\edwong\.netbeans\dev20080319-1206
  Installation            = C:\NB6\20080319-1205\nb6.1
                            C:\NB6\20080319-1205\ide9
                            C:\NB6\20080319-1205\java2
                            C:\NB6\20080319-1205\xml2
                            C:\NB6\20080319-1205\apisupport1
                            C:\NB6\20080319-1205\enterprise5
                            C:\NB6\20080319-1205\mobility8
                            C:\NB6\20080319-1205\profiler3
                            C:\NB6\20080319-1205\gsf1
                            C:\NB6\20080319-1205\ruby2
                            C:\NB6\20080319-1205\visualweb2
                            C:\NB6\20080319-1205\soa2
                            C:\NB6\20080319-1205\identity2
                            C:\NB6\20080319-1205\uml5
                            C:\NB6\20080319-1205\harness
                            C:\NB6\20080319-1205\cnd2
                            C:\NB6\20080319-1205\platform8
  Boot & Ext. Classpath   = C:\HawaiiMAIN\build-tools\jdk1.5.0_13\jre\lib\rt.jar;C:\HawaiiMAIN\build-tools\jdk1.5.0_13
\jre\lib\i18n.jar;C:\HawaiiMAIN\build-tools\jdk1.5.0_13\jre\lib\sunrsasign.jar;C:\HawaiiMAIN\build-tools\jdk1.5.0_13
\jre\lib\jsse.jar;C:\HawaiiMAIN\build-tools\jdk1.5.0_13\jre\lib\jce.jar;C:\HawaiiMAIN\build-tools\jdk1.5.0_13
\jre\lib\charsets.jar;C:\HawaiiMAIN\build-tools\jdk1.5.0_13\jre\classes;C:\HawaiiMAIN\build-tools\jdk1.5.0_13
\jre\lib\ext\dnsns.jar;C:\HawaiiMAIN\build-tools\jdk1.5.0_13\jre\lib\ext\localedata.jar;C:\HawaiiMAIN\build-
tools\jdk1.5.0_13\jre\lib\ext\sunjce_provider.jar;C:\HawaiiMAIN\build-tools\jdk1.5.0_13\jre\lib\ext\sunpkcs11.jar
  Application Classpath   = C:\NB6\20080319-1205\platform8\lib\boot.jar;C:\NB6\20080319-1205\platform8\lib\org-openide-
modules.jar;C:\NB6\20080319-1205\platform8\lib\org-openide-util.jar;C:/HawaiiMAIN/build-tools/jdk1.5.0_13
\lib\dt.jar;C:/HawaiiMAIN/build-tools/jdk1.5.0_13\lib\tools.jar
  Startup Classpath       = C:\NB6\20080319-1205\platform8\core\core.jar;C:\NB6\20080319-1205\platform8\core\org-
openide-filesystems.jar;C:\NB6\20080319-1205\nb6.1\core\org-netbeans-upgrader.jar;C:\NB6\20080319-1205\nb6.1
\core\locale\core_nb.jar
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