You can do that using another selector method called XPath. We don't have a UI for it in the sidebar, but you can enable it by editing the {click} command directly.
To do so, double click on the "click" command in the editor so it converts to text/code.
Then, replace the "selector=..." part, with "xpath=...".
The xpath you want is probably something like: //div[contains(text(), 'Verzend een e-mail')]