Mention the name of the software in the page title
GtkHash is not only a file manager extension
Simplify two sentences
Format at steps
Add missing step
Rephrase step

Avoid Saxon Genitive
Split steps
Rephrase steps

Use 'dialog', 'column', 'check box', and 'tabbed section' as per GDP guide
Add screenshot to clarify context
Avoid using 'this'
Improve phrasing
Rewrap