diff --git a/defaults/solr.keys.list b/defaults/solr.keys.list
index ed6392b50..bb33c44ac 100644
--- a/defaults/solr.keys.list
+++ b/defaults/solr.keys.list
@@ -111,6 +111,9 @@ attr_paths
 ## host of the url, string
 host_s
 
+## url inside the canonical link element, string
+canonical_s
+
 ## all texts in <li> tags, textgen
 attr_li
 
diff --git a/source/de/anomic/search/Switchboard.java b/source/de/anomic/search/Switchboard.java
index 6657def71..7da70867a 100644
--- a/source/de/anomic/search/Switchboard.java
+++ b/source/de/anomic/search/Switchboard.java
@@ -561,15 +561,21 @@ public final class Switchboard extends serverSwitch {
         TextParser.setDenyMime(getConfig(SwitchboardConstants.PARSER_MIME_DENY, ""));
 
         // prepare a solr index profile switch list
+        final File solrBackupProfile = new File("defaults/solr.keys.list");
         final File solrWorkProfile = new File(getDataPath(), "DATA/SETTINGS/solr.keys.default.list");
-        if (!solrWorkProfile.exists()) FileUtils.copy(new File("defaults/solr.keys.list"), solrWorkProfile);
-        final SolrScheme scheme = new SolrScheme(solrWorkProfile);
+        if (!solrWorkProfile.exists()) FileUtils.copy(solrBackupProfile, solrWorkProfile);
+        final SolrScheme backupScheme = new SolrScheme(solrBackupProfile);
+        final SolrScheme workingScheme = new SolrScheme(solrWorkProfile);
+
+        // update the working scheme with the backup scheme. This is necessary to include new features.
+        // new features are always activated by default
+
 
         // set up the solr interface
         final String solrurls = getConfig("federated.service.solr.indexing.url", "http://127.0.0.1:8983/solr");
         final boolean usesolr = getConfigBool("federated.service.solr.indexing.enabled", false) & solrurls.length() > 0;
         try {
-            this.solrConnector = (usesolr) ? new SolrChardingConnector(solrurls, scheme, SolrChardingSelection.Method.MODULO_HOST_MD5) : null;
+            this.solrConnector = (usesolr) ? new SolrChardingConnector(solrurls, workingScheme, SolrChardingSelection.Method.MODULO_HOST_MD5) : null;
         } catch (final IOException e) {
             Log.logException(e);
             this.solrConnector = null;
diff --git a/source/net/yacy/cora/services/federated/solr/SolrScheme.java b/source/net/yacy/cora/services/federated/solr/SolrScheme.java
index 7b548221a..7d6bd5513 100644
--- a/source/net/yacy/cora/services/federated/solr/SolrScheme.java
+++ b/source/net/yacy/cora/services/federated/solr/SolrScheme.java
@@ -181,6 +181,9 @@ public class SolrScheme extends ConfigurationSet {
             }
             addSolr(solrdoc, "htags_i", h);
 
+            // canonical tag
+            if (html.getCanonical() != null) addSolr(solrdoc, "canonical_s", html.getCanonical().toNormalform(false, false));
+
             // meta tags
             final Map<String, String> metas = html.getMetas();
             final String robots = metas.get("robots");
diff --git a/source/net/yacy/cora/storage/ConfigurationSet.java b/source/net/yacy/cora/storage/ConfigurationSet.java
index 3f2f1d176..3232fad1a 100644
--- a/source/net/yacy/cora/storage/ConfigurationSet.java
+++ b/source/net/yacy/cora/storage/ConfigurationSet.java
@@ -72,6 +72,7 @@ public class ConfigurationSet extends AbstractSet<String> implements Set<String>
         }
     }
 
+
     @Override
     public boolean isEmpty() {
         // a shortcut to a fast 'true' in case that we initialized the class without a configuration file
diff --git a/source/net/yacy/document/parser/html/ContentScraper.java b/source/net/yacy/document/parser/html/ContentScraper.java
index 908447d22..6e292d4cd 100644
--- a/source/net/yacy/document/parser/html/ContentScraper.java
+++ b/source/net/yacy/document/parser/html/ContentScraper.java
@@ -125,6 +125,7 @@ public class ContentScraper extends AbstractScraper implements Scraper {
     private CharBuffer content;
     private final EventListenerList htmlFilterEventListeners;
     private float lon, lat;
+    private MultiProtocolURI canonical;
 
     /**
      * {@link MultiProtocolURI} to the favicon that belongs to the document
@@ -167,6 +168,7 @@ public class ContentScraper extends AbstractScraper implements Scraper {
         this.lon = 0.0f;
         this.lat = 0.0f;
         this.evaluationScores.match(Element.url, root.toNormalform(false, false));
+        this.canonical = null;
     }
 
     public void scrapeText(final char[] newtext, final String insideTag) {
@@ -345,6 +347,10 @@ public class ContentScraper extends AbstractScraper implements Scraper {
                     final ImageEntry ie = new ImageEntry(newLink, linktitle, -1, -1, -1);
                     this.images.put(ie.url(), ie);
                     this.favicon = newLink;
+                } else if (rel.equalsIgnoreCase("canonical")) {
+                    final Properties p = new Properties(); p.put("name", this.title);
+                    this.anchors.put(newLink, p);
+                    this.canonical = newLink;
                 } else if (rel.equalsIgnoreCase("alternate") && type.equalsIgnoreCase("application/rss+xml")) {
                     this.rss.put(newLink, linktitle);
                 } else if (rel.equalsIgnoreCase("stylesheet") && type.equalsIgnoreCase("text/css")) {
@@ -599,6 +605,10 @@ public class ContentScraper extends AbstractScraper implements Scraper {
         return this.script;
     }
 
+    public MultiProtocolURI getCanonical() {
+        return this.canonical;
+    }
+
     /**
      * get all images
      * @return a map of <urlhash, ImageEntry>