They are all the same:
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config::begin("toolbtn","test1");
$cfg["tooltip"] = "TEST!";
config::end();
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config::begin("toolbtn");
$cfg["test1"]["tooltip"] = "TEST!";
config::end();
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config::begin();
$cfg["toolbtn"]["test1"]["tooltip"] = "TEST!";
config::end();
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$cfg_["toolbtn"]["test1"]["tooltip"] = "TEST!";
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