Yes, it works. Rated 5 out of 5 stars

Oops. Sorry, I tested 1.0.3 by mistake.
Yes, font-increasing works like a charm in 1.0.4. This instant updating is a cool feature.

Also this idea with FreeDictionary and Wikipedia is a great one, thanks a lot. But I couldn't figure out how to close the pop-up window with FreeDictionary and Wikipedia info. I don't see any close buttons there, and clicking on the background doesn't do anything.

Update: Ok, I got it. All I needed to do was to click the Tranquility button on the addon panel. Anyway, I think this should be more intuitive like clicking on the background, for example. )

This review is for a previous version of the add-on (1.0.4.1-signed.1-signed).  This user has 2 previous reviews of this add-on.

Re: wikipedia/freedictionary

Thanks for the feedback. You can hide the panel by either using Ctrl+Alt+W or Ctrl+Alt+D (the keyboard shortcuts should toggle that panel) too.

I'll work on the background click next; that is a good idea and I saw a similar comment from you for another addon review. So, I already have that on my list of things to do (will also get working on the custom background image shortly).

Update: I've submitted version 1.0.5 for preliminary review that hides the wikipedia/freedictionary panel when you click anywhere on the document outside the panel. You may have to wait a couple of days for the update to get approved and pushed.