For what it is, it works well. That being said, I decided to uninstall it for a few reasons...

1. Apparently, all the definitions are taken from a Google search. Granted the definitions themselves are fine, but it would be nice to have a larger pool of sources to choose from like Merriam-Webster or DuckDuckGo. Defaulting to Google works I suppose, but I don't think a Dictionary extension needs Google.

2. On that note, I can basically recreate the functionality of this extension using Swift Search Selection by adding a source like Miriam-Webster as a search engine, to say nothing of adding it as a search engine to the Firefox Browser itself.

Still gets the four stars because it is a good extension, but I decided since I already use SSS a lot anyway that I'll just keep using that and leave this on the shelf. Thanks for the good times.

Problem with all words searched giving "Sorry, no definition found." resolved idiopathically. I am running Linux with a VPN, though.
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Handy for words that you kind of know, but kind of know there's more to the definition.

Would be neat if you could toggle what the More>> link does. Thinking along the lines of a thesaurus library that could be accessed without opening a new search for "define xyz".

Though, the primary utility of the app seems to be in obtaining definitions with minimal interruption and task switching, so maybe less is more.

the popup is often overlapped by other popups. It doesn't have priority.

RE: Will fix this in next version, work is going on in this.

edit: I removed this add-on yesterday, because I noticed It never once turned out to be useful, even tho the popup always showed up and was annoying, and I always ignored it. I think it would be best to add an option for the popup to only show when you hold Alt or CTRL and double click.. Thanks.

RE: That option is already present, you can find it in extension options. :(. Can you try that and let me know?

edit2: I missed that option. Yeah it works! awesome!

Update: the extension stopped working lately. Sucks.
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Simple to use and it works. Double click on a word and you get a definition.

a simple add-on that does the job but is there any way to change the pronounciation to U.S. speaker?

Good Experience, This is what i was lookin for