Herzlich willkommen in der Delphi-PRAXiS, Sascha.
Hast du diesen Absatz auf der HomePage des Controls gesehen?
Zitat:
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How do I change preferences for the control, e.g. the proxy settings?
Edit the control profile's prefs.js and change the settings to those that you want.
Alternatively open about:config and configure the settings from there. You could also create a fresh profile in Mozilla / Firebird, change the settings from the preferences dialog and copy resultant the prefs.js over into the control's profile.
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Freundliche Grüße vom marabu