Swaps the default blue-based palette with a proper one. Thanks to https://learnui.design/tools/data-color-picker.html for the idea & color selection

google.analytics.palette.fixer.user.js

// ==UserScript==
// @name         Google Analytics color fixer
// @description  Swaps the default blue-based palette with a proper one. Thanks to https://learnui.design/tools/data-color-picker.html for the idea & color selection
// @version      0.4
// @author       You
// @match        https://analytics.google.com/analytics/web/*embed/report-home/*/
// @match        https://analytics.google.com/analytics/web/*
// @grant        GM_addStyle
// ==/UserScript==

var colors = ["#003f5c", "#2f4b7c", "#665191", "#a05195", "#d45087", "#f95d6a", "#ff7c43", "#ffa600"];
for(var i = 0; i < colors.length; i++) {
    GM_addStyle('stacked-bar-chart > svg > g:nth-child(2) > g.layer:nth-child('+(i+1)+') { fill: '+colors[i]+' !important; } ');
    GM_addStyle('pie-chart > svg > g.pie > path:nth-child('+(i+1)+') { fill: '+colors[i]+' !important; } ');
    GM_addStyle('ga-time-of-day-chart .legend-block.blue-'+(i+1)+' { fill: '+colors[i]+' !important; } ');
    GM_addStyle('ga-time-of-day-chart .blue-'+(i+1)+' rect { fill: '+colors[i]+' !important; } ');
    GM_addStyle('ga-d3-cohort-table .blue-'+(i+1)+' rect { fill: '+colors[i]+' !important; } ');
    GM_addStyle('ga-tabbed-chart stacked-bar-chart > svg g.layer:nth-child('+(i+1)+') { fill: '+colors[i]+' !important; } ');
}

(function() {
    'use strict';

    console.log("Started GA color fixer");

    /* TODO Replace timeout
    var MutationObserver = MutationObserver || WebKitMutationObserver || MozMutationObserver;
    var insertedNodes = [];
    var observer = new MutationObserver(function(mutations) {
        mutations.forEach(function(mutation) {
            for (var i = 0; i < mutation.addedNodes.length; i++)
                insertedNodes.push(mutation.addedNodes[i]);
        });
    });
    observer.observe(document, { childList: true });
    console.log(insertedNodes);


    setTimeout( function() {
        $('stacked-bar-chart > svg > g:nth-child(2) > g.layer').each(function () {
            //$(this).removeAttr('fill');
            console.log("Removed fills");
        });
    }, 4000);
    */
})();

---->

Credits: https://learnui.design/tools/data-color-picker.html