Wordcount extension

[ChristianeLink]

Hi, I am new to Vivaldi. I just changed from Chrome. I am a journalist using an extension called Word Count tool - http://wordcounttools.com In Chrome a button appears in the top bar after installation. When I select text in the browser, click on the button, I get the number of words and characters. Unfortunately the button doesn't appear after installation in Vivaldi. I have restarted Vivaldi already. Any ideas or is it a bug? Thank you!