kibana-7.7.0-windows-x86_64\src\core\server\rendering\views\template.js
edit file and replace
const logo = _react.default.createElement("svg", {
xmlns: "http://www.w3.org/2000/svg",
width: "32",
height: "32",
viewBox: "0 0 32 32"
}, _react.default.createElement("g", {
fill: "none"
}, _react.default.createElement("path", {
fill: "#FDD009",
d: "M11.9338171,13.1522761 L19.2872353,16.5080972 L26.7065664,10.0005147 C26.8139592,9.46384495 26.866377,8.92859725 26.866377,8.36846422 C26.866377,3.78984954 23.1459864,0.0647302752 18.5719941,0.0647302752 C15.8357526,0.0647302752 13.2836129,1.41337248 11.7323847,3.67480826 L10.4983628,10.0839872 L11.9338171,13.1522761 Z"
}), _react.default.createElement("path", {
fill: "#23BAB1",
d: "M4.32214501,20.9473399 C4.21475229,21.4841518 4.1596354,22.0410142 4.1596354,22.6044179 C4.1596354,27.1948353 7.89096419,30.9300509 12.4774572,30.9300509 C15.2361432,30.9300509 17.8007837,29.5687528 19.3495969,27.2841381 L20.5743853,20.8965739 L18.9399136,17.7698399 L11.5573744,14.401505 L4.32214501,20.9473399 Z"
}), _react.default.createElement("path", {
fill: "#EE5097",
d: "M4.27553714,8.20847294 L9.31503995,9.3995555 L10.4190826,3.6639867 C9.73040545,3.1371289 8.88035513,2.84874358 8.00601361,2.84874358 C5.81596922,2.84874358 4.0348979,4.63252339 4.0348979,6.82484908 C4.0348979,7.30904633 4.11572655,7.77333532 4.27553714,8.20847294"
}), _react.default.createElement("path", {
fill: "#17A7E0",
d: "M3.83806807,9.40996468 C1.58651435,10.1568087 0.0210807931,12.3172812 0.0210807931,14.6937583 C0.0210807931,17.0078087 1.45071086,19.0741436 3.5965765,19.8918041 L10.6668813,13.494428 L9.36879313,10.717795 L3.83806807,9.40996468 Z"
}), _react.default.createElement("path", {
fill: "#92C73D",
d: "M20.6421734,27.2838537 C21.3334075,27.8156885 22.1793383,28.1057803 23.0428837,28.1057803 C25.232786,28.1057803 27.0138574,26.3228537 27.0138574,24.130528 C27.0138574,23.6470417 26.9331708,23.1827528 26.7732181,22.7477573 L21.7379769,21.5681931 L20.6421734,27.2838537 Z"
}), _react.default.createElement("path", {
fill: "#0678A0",
d: "M21.6667227,20.2469532 L27.2099485,21.5446872 C29.4623545,20.7995495 31.0277881,18.6382239 31.0277881,16.2608936 C31.0277881,13.9511092 29.5947487,11.8871917 27.4447635,11.0719486 L20.1946185,17.4303615 L21.6667227,20.2469532 Z"
})));
by
const logo = _react.default.createElement("img", {src:'http://logo.ico',width:'80px'});
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