So, here´s the English version for what Juan Pablo explained in Spanish.
Sometimes, you need to finish some translation in another computer and you don´t have the Editor installed. Well, that´s not an obstacle for not completing your work!
1) You go to the link from where you would download the mxliff to be opened with your Editor,
2) and instead of downloading it, you just double click on the file, and the file will open in another tab. (just make sure to unblock "Pop-ups")
3) You´ll see a similar interphase as the Editor, slightly more basic, but you could perfectly work on it in a similar way as you do in the Editor.
I hope the screenshot helps: