A spreadsheet that contains colors, borders and other formatting but no
characters or numbers is not recognized with content. Therefore nothing is
displayed via menu "File - Page Preview". Howver, it is shown via "View - Page
Break Preview".

Just put a character or number into a cell and it is shown in the Page preview, too.

Suggestion:

Recognize cell backgrounds and cell borders as content. In order to aviod
printing when this is applied to complete columns and rows, we have to consider
a special algorithm. Excel seems to take the last cell horizontal/vertical that
has own attribute resp. content. Without it shows just ~5 cells of the
column/row that have attributes. Maybe it's nice to show just all cells that fit
on the first page.

However, at the end the preview should also display cell formatting when no
other content is existing.

Is there anything else that needs to be considered?