This menu popup can you use to work with document and clipboard...

Undo
Redo
Copy
Cut
Paste
Delete
Select all
Maximize window
Minimize window

Undo - undoes last action you've done. This function is applicable to images and texts after you change opened file...
Redo - redoes action, that you've undoed using undo command.
Copy - copies selected part of image/text/binary file to clipboard
Cut - copies selected part of image/text/binary file to clipboard and removes it from document
Paste - inserts clipboard's data to document in the place of cursor (text, binary files) or replaces active document with document placed in clipboard
Delete - removes selected part of document
Select all - selects whole document
Maximize window - maximizes size of UniView window
Minimize window - minimizes size of UniView window