Not all properties are visible in the page template and can be edited using PropertyFor helper. Some of them have to be edited through All Properties mode. I thought that it would be useful for editors to have quick access to some properties in On Page Edit. I introduced a way of adding additional header properties.
additional header properties

By default Episerver allows to add properties to header panel by using “EPiServerCMS_SettingsPanel” group name. To add property to this group we can use EPiServer.DataAbstraction.SystemTabNames.PageHeader constant.

Those properties are displayed in the first header column.

header properties in first column

But usually there is enough space on the right to show additional properties and avoid increasing header height.

To add header property you need to add OpeHeadingProperty attribute on content model.

Properties can be added to First or Third column.
For example “Display in navigation” is added to first column and “Show header” and “Number of articles” are in third column.
using header properties

For smaller screens, third column will automatically fall under first column. Same as second column.

header properties very small screens

In All Properties mode, all additional properties are not displayed in header, but in the tabs. For example “Number of articles” property, in All Properties mode, is displayed under Content tab.
header properties in APE

When switching between On Page Edit and All Properties, “Number of articles” is added and removed from header.

All properties mode

The source code is available on Github