Comment 1 for bug 339506

There is an overview page for a user for every PO file (containing all the translations that person has submitted, including discarded suggestions). To see them, go to the "Overview" tab for a PO file, and then click on "filter" next to the user's name. From there, you can click the number which will take you to the "zoomed in" view for the message you are looking at, and do your changes there.

I know this is not exactly what you are asking for, but should be able to solve the problems you are running into, without adding more clutter to the UI for something that would be rarely used.

If this is not enough, let's discuss the problem and try to find a better solution to it. Is the functionality above suitable?