Hello,
Thank you for the example. It pointed me in the right direction. The HTML file it produces works fine in Chrome - I get the tabs across the bottom and can click them to switch between the worksheets.
The program I am developing uses the classic ActiveX WebBrowser control (with registry settings to have it use IE11) to display the converted workbook. IE is finding the '
mark of the web' in the top level webpage, and preventing the Tabs frame from loading, as it contains javascript. Therefore, the WebBrowser displays the active worksheet but not the tab area, leading to my initial, incorrect conclusion.
I think I can take it from here, possibly by just removing the mark of the web line.