Hi Marcel
It's possibly the SAPLogon.INI file or if a newer version of the GUI, an XML file

I'm on SAP GUI 770 and for me it's the SAPUILandscape.xml file. It's in the SAP Logon pad -> Options -> SAP Logon Options and then path to local configuration files.
Typically IT or Basis will share that file with SAP users, but you can do so, as well.
Or, the users can use the article Archana shared to add them manually - but sharing the file is simplest.
You can also point to that directory in Studio under Options -> SAP Settings

Hope that helps,
Sigrid
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Sigrid Kok
Precisely Software Inc.
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