Item conversion contact <-> number [Homematic]

I use a homematic HMW-IO-12-Sw14-DR and a HMW-Sen-SC-12-DR, both for digital inputs atachted to my window contacts.
Sw14-DR inputs are available as Number (1/0), SC-12-DR as Contact (open/closed)
In my configuration that reads as

Contact         EG_Wohnen_FensterSuedWest    "Fenster_Wohnen SüdWest [MAP(]"   <window>          (gEG_Wohnen, gFensterContact, gFenster)   ["Window"]                       {channel="homematic:HMW-Sen-SC-12-DR:ccu:KEQ0001111:9#SENSOR"}
Number         EG_Flur_Fenster               "Fenster_Flur [MAP(]"      <window>          (gEG_Flur, gFensterNumber, gFenster)         ["Window"]           {channel="homematic:HMW-IO-12-Sw14-DR:ccu:MEQ0801111:17#STATE"}

The map feature converts both, however, in the mainGUI they behave differently.
The number items can be displayed over time, the contact items can’t if you click on them (mind the “>” ) :

Is there something that I am missing ? Maybe a cast of Contact to Number on a thing / channel level ?