diff --git a/.eslintrc.json b/.eslintrc.json
index 49f82e81c56..55db8c49169 100644
--- a/.eslintrc.json
+++ b/.eslintrc.json
@@ -16,6 +16,7 @@
   },
   "globals": {
     "cy": true,
+    "before": true,
     "context": true,
     "Cypress": true,
     "assert": true
diff --git a/extensions/dicom-html/src/ConnectedDicomHtmlViewport.js b/extensions/dicom-html/src/ConnectedDicomHtmlViewport.js
new file mode 100644
index 00000000000..9e66b0b7419
--- /dev/null
+++ b/extensions/dicom-html/src/ConnectedDicomHtmlViewport.js
@@ -0,0 +1,33 @@
+import OHIF from '@ohif/core';
+import { connect } from 'react-redux';
+import DicomHtmlViewport from './DicomHtmlViewport';
+
+const { setViewportActive } = OHIF.redux.actions;
+
+const mapStateToProps = (state, ownProps) => {
+  const { viewportIndex, byteArray } = ownProps;
+  const activeViewportIndex = state.viewports;
+
+  return {
+    viewportIndex,
+    activeViewportIndex,
+    byteArray,
+  };
+};
+
+const mapDispatchToProps = (dispatch, ownProps) => {
+  const { viewportIndex } = ownProps;
+
+  return {
+    setViewportActive: () => {
+      dispatch(setViewportActive(viewportIndex));
+    },
+  };
+};
+
+const ConnectedDicomHtmlViewport = connect(
+  mapStateToProps,
+  mapDispatchToProps
+)(DicomHtmlViewport);
+
+export default ConnectedDicomHtmlViewport;
diff --git a/extensions/dicom-html/src/DicomHtmlViewport.js b/extensions/dicom-html/src/DicomHtmlViewport.js
index 686c0057bd7..1008d92cd75 100644
--- a/extensions/dicom-html/src/DicomHtmlViewport.js
+++ b/extensions/dicom-html/src/DicomHtmlViewport.js
@@ -1,6 +1,8 @@
 import React, { Component } from 'react';
+import PropTypes from 'prop-types';
 import * as dcmjs from 'dcmjs';
 import TypedArrayProp from './TypedArrayProp';
+
 import './DicomHtmlViewport.css';
 
 function getRelationshipString(data) {
@@ -30,7 +32,7 @@ function getValueString(data) {
       const {
         CodeMeaning,
         CodeValue,
-        CodingSchemeDesignator
+        CodingSchemeDesignator,
       } = data.ConceptNameCodeSequence;
 
       return `${CodeMeaning} (${CodeValue}, ${CodingSchemeDesignator})`;
@@ -75,7 +77,7 @@ function constructContentSequence(data, header) {
   }
 
   const result = {
-    items
+    items,
   };
 
   if (header) {
@@ -106,9 +108,7 @@ const { DicomMetaDictionary, DicomMessage } = dcmjs.data;
 function getMainData(data) {
   const root = [];
 
-  const patientValue = `${data.PatientName} (${data.PatientSex}, #${
-    data.PatientID
-  })`;
+  const patientValue = `${data.PatientName} (${data.PatientSex}, #${data.PatientID})`;
   root.push(getMainDataItem('Patient', patientValue));
 
   const studyValue = data.StudyDescription;
@@ -117,15 +117,13 @@ function getMainData(data) {
   const seriesValue = `${data.SeriesDescription} (#${data.SeriesNumber})`;
   root.push(getMainDataItem('Series', seriesValue));
 
-  const manufacturerValue = `${data.Manufacturer} (${
-    data.ManufacturerModelName
-  }, #${data.DeviceSerialNumber})`;
+  const manufacturerValue = `${data.Manufacturer} (${data.ManufacturerModelName}, #${data.DeviceSerialNumber})`;
 
   root.push(getMainDataItem('Manufacturer', manufacturerValue));
 
   const mainDataObjects = {
     CompletionFlag: 'Completion flag',
-    VerificationFlag: 'Verification flag'
+    VerificationFlag: 'Verification flag',
   };
 
   Object.keys(mainDataObjects).forEach(key => {
@@ -154,7 +152,7 @@ const getContentSequence = (data, level = 1) => {
     const {
       CodeMeaning,
       CodeValue,
-      CodingSchemeDesignator
+      CodingSchemeDesignator,
     } = data.ConceptNameCodeSequence;
 
     header = `${CodeMeaning} (${CodeValue} - ${CodingSchemeDesignator})`;
@@ -198,11 +196,14 @@ function getMainDataItem(key, value) {
 class DicomHtmlViewport extends Component {
   state = {
     content: null,
-    error: null
+    error: null,
   };
 
   static propTypes = {
-    byteArray: TypedArrayProp.uint8
+    byteArray: TypedArrayProp.uint8,
+    setViewportActive: PropTypes.func.isRequired,
+    viewportIndex: PropTypes.number.isRequired,
+    activeViewportIndex: PropTypes.number.isRequired,
   };
 
   componentDidMount() {
@@ -225,15 +226,34 @@ class DicomHtmlViewport extends Component {
     );
 
     this.setState({
-      content
+      content,
     });
   }
 
+  setViewportActiveHandler = () => {
+    const {
+      setViewportActive,
+      viewportIndex,
+      activeViewportIndex,
+    } = this.props;
+
+    if (viewportIndex !== activeViewportIndex) {
+      setViewportActive();
+    }
+  };
+
   render() {
+    const { content, error } = this.state;
+
     return (
-      <div className={'DicomHtmlViewport'}>
-        {this.state.content}
-        {this.state.error && <h2>{JSON.stringify(this.state.error)}</h2>}
+      <div
+        data-cy="dicom-html-viewport"
+        className="DicomHtmlViewport"
+        onClick={this.setViewportActiveHandler}
+        onScroll={this.setViewportActiveHandler}
+      >
+        {content}
+        {error && <h2>{JSON.stringify(error)}</h2>}
       </div>
     );
   }
diff --git a/extensions/dicom-html/src/OHIFDicomHtmlViewport.js b/extensions/dicom-html/src/OHIFDicomHtmlViewport.js
index 0d9e26557a1..bd804981151 100644
--- a/extensions/dicom-html/src/OHIFDicomHtmlViewport.js
+++ b/extensions/dicom-html/src/OHIFDicomHtmlViewport.js
@@ -1,7 +1,8 @@
 import React, { Component } from 'react';
 import PropTypes from 'prop-types';
-import DicomHtmlViewport from './DicomHtmlViewport';
 import OHIF from '@ohif/core';
+import ConnectedDicomHtmlViewport from './ConnectedDicomHtmlViewport';
+
 const { DicomLoaderService } = OHIF.utils;
 
 class OHIFDicomHtmlViewport extends Component {
@@ -9,6 +10,7 @@ class OHIFDicomHtmlViewport extends Component {
     studies: PropTypes.object,
     displaySet: PropTypes.object,
     viewportIndex: PropTypes.number,
+    viewportData: PropTypes.object,
   };
 
   state = {
@@ -40,7 +42,10 @@ class OHIFDicomHtmlViewport extends Component {
     return (
       <>
         {this.state.byteArray && (
-          <DicomHtmlViewport byteArray={this.state.byteArray} />
+          <ConnectedDicomHtmlViewport
+            byteArray={this.state.byteArray}
+            viewportIndex={this.props.viewportIndex}
+          />
         )}
         {this.state.error && <h2>{JSON.stringify(this.state.error)}</h2>}
       </>
diff --git a/platform/viewer/cypress/integration/pwa/OHIFExtensionHTML.spec.js b/platform/viewer/cypress/integration/pwa/OHIFExtensionHTML.spec.js
index 08757cec9e7..6249392510f 100644
--- a/platform/viewer/cypress/integration/pwa/OHIFExtensionHTML.spec.js
+++ b/platform/viewer/cypress/integration/pwa/OHIFExtensionHTML.spec.js
@@ -22,4 +22,23 @@ describe('OHIF HTML Extension', () => {
       'Imaging Measurement Report'
     );
   });
+
+  it('checks if the HTML viewport has been set to active by interaction', () => {
+    cy.setLayout('3', '3');
+
+    // check if viewport has been set as active by CLICKING
+    cy.get('[data-cy=viewprt-grid] > :nth-child(4)')
+      .click()
+      .then($viewport => {
+        cy.wrap($viewport).should('have.class', 'active');
+      });
+
+    // check if viewport has been set as active by SCROLLING
+    cy.get('[data-cy=viewprt-grid] > :nth-child(7)').then($viewport => {
+      cy.wrap($viewport)
+        .find('[data-cy=dicom-html-viewport]')
+        .scrollTo('bottom');
+      cy.wrap($viewport).should('have.class', 'active');
+    });
+  });
 });
diff --git a/platform/viewer/cypress/support/commands.js b/platform/viewer/cypress/support/commands.js
index b2a2ba846ea..4fa5be9eb4f 100644
--- a/platform/viewer/cypress/support/commands.js
+++ b/platform/viewer/cypress/support/commands.js
@@ -328,6 +328,21 @@ Cypress.Commands.add('percyCanvasSnapshot', (name, options = {}) => {
   });
 });
 
+Cypress.Commands.add('setLayout', (columns = 1, rows = 1) => {
+  cy.get('.toolbar-button-label')
+    .contains('Layout')
+    .click();
+
+  cy.get('.layoutChooser')
+    .find('tr')
+    .eq(rows - 1)
+    .find('td')
+    .eq(columns - 1)
+    .click();
+
+  cy.wait(1000);
+});
+
 function convertCanvas(documentClone) {
   documentClone
     .querySelectorAll('canvas')
@@ -364,4 +379,4 @@ function canvasToImage(selectorOrEl) {
   canvas.setAttribute('data-percy-canvas', true);
   canvas.parentElement.appendChild(image);
   canvas.style = 'display: none';
-}
\ No newline at end of file
+}