| Index: _locales/en_US/messages.json | 
| =================================================================== | 
| --- a/_locales/en_US/messages.json | 
| +++ b/_locales/en_US/messages.json | 
| @@ -187,5 +187,25 @@ | 
| "whitelisted_domains": { | 
| "description": "This is a tab heading.", | 
| "message": "Whitelisted domains" | 
| +  }, | 
| +  "unexpected_filter_list_header": { | 
| +    "message": "Filter list headers aren't allowed here" | 
| +  }, | 
| +  "invalid_css_selector": { | 
| +    "message": "$selector$ is not a valid CSS selector", | 
| +    "placeholders": { | 
| +      "selector": { | 
| +        "content": "$1" | 
| +      } | 
| +    } | 
| +  }, | 
| +  "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" | 
| +      } | 
| +    } | 
| } | 
| } | 
|  |