Open Hyperlinks without using control key

Dear Forum,
I need to know where I can change the way how to open hyperlinks. By default it works with control and mouse click. I once changed this, so just the mouse click alone opened hyperlinks, bur unfortunately I can't remember where this option is hiding and I need to redo this setting since it got lost.
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Please can anyone help me to find this option? My version is 7.1.42 portable. Thanks a lot in advance.