How to show up bitmaps when revisiting editing OCR?

[mpek]

I started to OCR from an mkv made from DVD with Bitmap/PGS german subtitle.
When making a break and restarting computer and continuing to work on the project, by clicking on Spell check, how can I show up again the bitmaps as a reference when editing the text?
When starting this process as new I can see the bitmaps while editing the position in question.

[niksedk]

Try the context menu:

[mpek]

Ah okay, nice to know. Why is that hidden? :)
Would need another hint: Where is that file being saved, when I imported the image based subtitle from a video file (mkv)?

[niksedk]

He, in case of mkv, you would need to right-click in the OCR list view and export subs...