No default property tree is set for specification type &1

What causes this issue?

No default property tree is set for the specification type &v1&
specified. The property tree &v2& is therefore displayed.

Procedure for System Administrators

If required, specify a default property tree in the Specification Type
detail screen in the IMG activity <DS:SIMG.EHS_MD_110_05_1>Specify
Specification Types</>.
Note for translation: The following lines
have been copied from CM_SUB_DATA015.
If no default property tree has been specified and no user settings
have been defined, the SAP System uses the property tree for which the
<LS>Default property tree for specification management</> indicator has
been set in the IMG activity <LS>Set Up Property Trees</>.

Error message extract from SAP system. Copyright SAP SE.