You can re-insert hidden attributes into the Attributes tab or the Properties - Attributes dialog box.
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1. Click on More attributes.
2. Open the attribute type group in which the attributes you want to insert are stored.
3. Select one or more attribute types.
4. Click OK.
The attributes are displayed in the attribute list again.
If you want to insert only one attribute type, double-click on the desired item. The dialog box is closed and the attribute type is inserted into the list.