Although that I this is a very interesting extension and can be a time saver to many text writing users on the web, I gave only 3 stars because it can ONLY replace text and symbols in the text box of "Google translate" website only. It doesn't work on any other website, or Addon/extension which have full/or pop up text page input window. Also it takes two steps to do this job, whereas other similar Addons do this with one-click of the button. (here you must click the addon on the toolbar, click Replace from the list, and after a Sidebar will open on the right side of the window... which is too much of actions to do).
-> For now I will go with the two similar addons which are very convenient to me. Those are: ◾ Replace by erosman and the ◾ Find & Replace for Text Editing by Dalimil Hajek.
Fix this problem (to be able to replace text everywhere and make the process in only one step), and I will give 5 stars on my rating.