Bug 1513076 - Do Not Track string change for Firefox 65. r=flod

Differential Revision: https://phabricator.services.mozilla.com/D14104

--HG--
extra : moz-landing-system : lando

browser/components/preferences/in-content/privacy.xul

@@ -198,7 +198,7 @@
       data-l10n-id="do-not-track-learn-more"></label></label>
       <radiogroup id="doNotTrackRadioGroup" aria-labelledby="doNotTrackDesc" preference="privacy.donottrackheader.enabled">
         <radio value="true" data-l10n-id="do-not-track-option-always"/>
-        <radio value="false" data-l10n-id="do-not-track-option-default-content-blocking"/>
+        <radio value="false" data-l10n-id="do-not-track-option-default-content-blocking-known"/>
       </radiogroup>
     </vbox>
   </vbox>

browser/locales/en-US/browser/preferences/preferences.ftl

@@ -4,8 +4,8 @@
 
 do-not-track-description = Send websites a “Do Not Track” signal that you don’t want to be tracked
 do-not-track-learn-more = Learn more
-do-not-track-option-default-content-blocking =
-    .label = Only when { -brand-short-name } is set to block Detected Trackers
+do-not-track-option-default-content-blocking-known =
+    .label = Only when { -brand-short-name } is set to block known trackers
 do-not-track-option-always =
     .label = Always