Quick-edit
Quick-edit is one of the most frequent used features that allows you to edit a certain page, edit in the history page, edit the certain section f the certain page, or even edit a certain section from an old revision, without opening a new tab.
Use via toolbox
Click, and it's done!
Edit a section via link beside the heading
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Use it while browsing the page history
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Use it when using quick-diff
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