Windows-Einstellungen -> System -> Benachrichtigungsassistent -> "Wenn ich spiele" auf Aus schlaten
Eng.:
The Windows 10 April 2018 Update introduced a new feature which leads to slow tabbing, starting and closing of Settlers 3 and other Fullscreen games. To fix this issue navigate to:
Windows Settings -> System -> Focus Assist -> switch "When I’m playing games" to off
Hint
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