diff --git a/sphinx/index.rst b/sphinx/index.rst
index e7f5680..713821c 100644
--- a/sphinx/index.rst
+++ b/sphinx/index.rst
@@ -35,24 +35,6 @@ Welcome to the **EMMO Electrochemistry Domain Ontology**, a semantic resource wi
             }
          }
 
-   .. tab-item:: JSON Crack
-
-      .. raw:: html
-            
-         <div style="position: relative; padding-top: 56.25%;">  <!-- Aspect ratio of 16:9 -->
-            <iframe id="jsoncrackEmbed" style="position: absolute; top: 0; left: 0; width: 100%; height: 100%;" src="https://jsoncrack.com/widget?json=https://raw.githubusercontent.com/emmo-repo/domain-electrochemistry/master/sphinx/assets/jsonld/example_electrochemical_cell.json"></iframe>
-         </div>
-
-   .. tab-item:: JSON-LD Playground
-
-      .. raw:: html
-            
-         <div style="position: relative; padding-top: 56.25%;">  <!-- Aspect ratio of 16:9 -->
-            <iframe src="https://json-ld.org/playground/#startTab=tab-expanded&json-ld=%7B%22%40context%22%3A%22https%3A%2F%2Fraw.githubusercontent.com%2Femmo-repo%2Fdomain-electrochemistry%2Fmaster%2Fcontext.json%22%2C%22%40type%22%3A%22ElectrochemicalCell%22%2C%22hasNegativeElectrode%22%3A%7B%22%40type%22%3A%22ZincElectrode%22%7D%2C%22hasPositiveElectrode%22%3A%7B%22%40type%22%3A%22ManganeseDioxideElectrode%22%7D%2C%22hasElectrolyte%22%3A%7B%22%40type%22%3A%22AlkalineElectrolyte%22%7D%7D" style="position: absolute; top: 0; left: 0; width: 100%; height: 100%;" frameborder="0" allowfullscreen></iframe>
-         </div>
-
-
-
 Check out these resources to get started!
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 .. grid::