The plugin collects all the text as requested and you can quickly jump to the location by double-clicking the location (and then edit). Furthermore, if the lines have numbering, then you can mark whether the text is correct or not. You can also sort, filter the lines and find text.
I haven't added in-grid editing yet, so it will require to double-click in order to fix the text. Editing requires covering many use cases (the editor doesn't help much here since there is no option to know if it has pending edits or even if the script is open), but it's certainly possible. I simply assumed that if someone proof reads, the majority of the text is correct and therefore there won't be that many double clicks. However, if that feature is of more use I can work on getting that earlier than translations.
thiezar, I suggest you give me feedback as to whether the existing features are helpful enough (I know of at least one other person who used the plugin for proof reading purposes). If you find yourself with many edits and therefore the current method slows you down, I'll switch priorities.