Thumbnails not available in spreadsheet editor

Multiple customers have requested thumbnails in the spreadsheet editor. A thumbnail can be used as a column in the workspace/folder view and is a common practice. When a thumbnail is used as a column in the workspace/folder view and a user opens the spreadsheet editor, the thumbnail column simply does not show. This is poor user experience because a user may expect the column to be there, since the columns in the spreadsheet editor should follow what is in the workspace/folder view. Additionally, many implementations may use thumbnails instead of a typical title, so the user may not be able to know what document they are editing from the spreadsheet view without the thumbnails.

Please backport this functionality to previous versions of the platform-spreadsheet.