RTC: Where is the last used Company stored?

Does anybody know where the last used Company is stored? Unforutntly it's not in the ClientUserSettings.config:

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
	<appSettings>
  <add key="Server" value="" />
  <add key="ServerInstance" value=" />
  <add key="ServerPort" value="" />
  <add key="ProtectionLevel" value="EncryptAndSign" />
  <add key="UrlHistory" value="" />
  <add key="CompressionThreshold" value="64" />
  <add key="ChunkSize" value="28" />
  <add key="AllowNtlm" value="true" />
  <add key="ServicePrincipalNameRequired" value="False" />
  <add key="OpenConnectionTimeout" value="00:00:30" />
  <add key="UnknownSpnHint" value="" />
 </appSettings>
</configuration>