registerOnSelectCallback not firing

Hi,

Using the information provided on Handling Visual Selection I did successfully implement cross-selection in my custom Visual using the SelectionBuilder and SelectionManager objects. Since all of the code is working fine I also wanted to implement support for Bookmarks. I added the following line of code to the constructor of the custom Visual

this.selectionManager.registerOnSelectCallback( () => {
    console.log("registerOnSelectCallback");
});

Next I tried to highlight some data points in my Visual while each time adding a new Bookmark. If I then go back to the Bookmarks  it never seems to work as there is no console.log in the output. Also adding a debugger; statement does not cause the debugger to break.

Is there anything that needs to be done to get Bookmarks working? 

Thanks

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