WebStatistica Spreadsheet Editor requires Java installation and needs to use Java through the web browsers. 
https://support.tibco.com/s/article/What-operations-in-WebStatistica-require-Java
We recommend users using Internet Explorer (IE) browser as it supports Java plugin. 

Starting with Chrome Version 42 (released April 2015), Google has removed the support for Java plugin in their Chrome web browser.
When logging in to WebStatistica through Chrome and creating a new spreadsheet with WebStatistica spreadsheet Editor, below is what you may get with Chrome: The spreadsheet editor is not displayed. 



Is it then possible to open WebStatistica Java Spreadsheet Editor in Google Chrome?

Is it possible to open WebStatistica Java Spreadsheet Editor in Google Chrome?

Windows

If you want to use Java in Chrome browser, this article may provide a feasible way:  https://www.digitalcitizen.life/how-enable-java-all-major-web-browsers
The user can install a Chrome browser extension called "IE Tab", which allows you uses the Internet Explorer engine to display web pages in Google Chrome. 
"Each time you visit a web page with Java that does not work correctly in Google Chrome, click or tap the "e" button from the top-right corner of Chrome. It opens a new IE Tab tab that uses the Internet Explorer engine, with support for Java. "

Below is what you can do if you want to use WebStatistica spreadsheet editor in Chrome:
1. Download Java through Internet Explorer (IE) browser, and Install Java.
Follow instructions in this article  https://support.tibco.com/s/article/Statistica-Server-The-page-you-are-viewing-uses-Java to enable Java plugin when accessing WebStatistica spreadsheet editor from Internet Explorer (IE) browser. 
Make sure the IE browser is able to display the WebStatistica spreadsheet editor with Java plugin:


2. Follow above article  https://www.digitalcitizen.life/how-enable-java-all-major-web-browsers to install and configure "IE Tab" extension for Chrome browser. 
Open WebStatistica in Chrome, click on "e" to load the webpage through IE engine and display it in Chrome.
Create a new spreadsheet in WebStatistica and the spreadsheet editor is being displayed in Chrome.


NOTE:
Though this is a feasible way to use Chrome to access WebStatistica spreadsheet editor, it is still using the IE engine to run the Java plugin to display the editor.