Distill's drop icon not visible in Firefox toolbar

I installed the Distill Web Monitor add-on in Firefox, but there is no drop icon :frowning:
What can be the reason?

Can you check if you need to ping the extension to the toolbar? Checkout the following screenshot to know how to do that:

Many thanks for the answer, but I don’t see “Pin to Toolbar”.
I am using Firefox in Windows 10.

Can you share a screenshot of what you see?