Issue 4349 - Updated short description to reflect that Adblock Plus is used on over 100M active devi

_locales/en_US/messages.json

 {
   "add": {
     "description": "This is the label for the 'Add' buttons.",
     "message": "Add"
   },
   "add_domain_button": {
     "message": "Add domain"
   },
   "add_filter_button": {
     "message": "Add filter"
@@ skipping 14 matching lines @@
   "cancel": {
     "description": "Cancel button label",
     "message": "Cancel"
   },
   "clickhide_instructions": {
     "description": "Instructions shown in popup UI before it disapears, when \"Block element\" action is executed",
     "message": "After closing this popup, click (or right-click) an element on the page."
   },
   "description": {
     "description": "Note: this cannot be longer than 132 characters",
-    "message": "Used by over 50 million people, a free ad blocker that blocks ALL annoying ads, malware and tracking."
+    "message": "Used on over 100 million devices, Adblock Plus is the world's most popular ad blocker."
   },
   "disabled_for_site":
   {
     "description": "Popup balloon label to disable blocking",
     "message": "<strong>Disabled</strong> on this site"
   },
   "disabled_for_these_domains": {
     "message": "Adblock Plus is disabled for the domains listed below. You can add a domain either via the Adblock Plus icon in the address bar or by typing the domain (not a URL) in the box and clicking the \"Add domain\" button."
   },
   "easy_create_filter": {
@@ skipping 158 matching lines @@
   "line": {
     "message": "Line $number$",
     "description": "Prepended to error messages to indicate the line number (e.g. \"Line 42: Some error on this line\")",
     "placeholders": {
       "number": {
         "content": "$1"
       }
     }
   }
 }