Select multiple: Don't show name of Select list (multiple selection) property when editing

Description

Step to reproduce

1. Go to Admin mode/Content Type.
2. Select a page type (for example: Standard page) > Add Property: Select list (multiple selection).
3. On this page type, select the 'Select list' property > open Custom settings tab > Check Use custom settings.
4. Add a name and value for settings > Save the change > the 'Select list' list has value.
5. Go to Edit mode and create a standard page.
6. View this page in All properties mode.
7. Select the 'Select list' property.

Expected: Shows the list name of custom settings for the property. Then, the user can select multiple items.
Actual: There is no value.

Note: Don't see issue on CMS 10.0