Spreadsheet Documents Merge Method
The dialog box is intended to select the mode of merging spreadsheet documents.
Selecting "Include content of both documents" means that the resulting document will include both documents. First it will contain the content of the document from the compared configuration and then after the "Merged part" separator it will contain the content of the document from the main configuration.
Selecting "Merge documents content" means that the resulting document will contain the merger result taking into account the specified priorities.