Non-existing support, zero reaction from the dev. in the posts on Github, zero consideration for the issues brought to his attention.

The addon has been updated many times and still the dev couldn't find time to make a freaking simple improvement like introducing a time limit for the button which appears when you select text.
A button that right now stays there FOREVER until you click somewhere else in the page, which is NOT always the case (for example, if you copy something to attach it in another page. Simple case: I copied the title of a movie I was streaming, so to write it to someone in an email. When I went back to the streaming, the freaking button was there in the mid of the freaking video. This is RIDICULOUS and one of the most blatant examples of atrocious UX Design.

It's so annoying that it escapes my comprehension how people give this thing 5 stars.