Google meet script to get a list of who has already talked during a daily meeting.

whoHasTalked.js

// ==UserScript==
// @name         Who has talked?
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Show a list of attendees to see who has already talked. Click on a name to remove it. Double click on the list to remove the overlay.
// @author       You
// @match        https://meet.google.com/*
// @grant        none
// ==/UserScript==

(function () {
    displayNameList();

    /**
     * Fetch names from the main window
     */
    function fetchVisibleNames() {
        const elements = document.querySelectorAll('div[data-self-name]');
        let names = [];

        for (let element of elements) {
            names.push(element.textContent);
        }

        return names
            .filter((currentValue, currentIndex, elements) => {
                return currentIndex === elements.indexOf(currentValue);
            })
            .sort();
    }

    /**
     * Fetch names from the name list
     */
    function fetchNamesFromUserList() {
        const nameElements = [
            ...document.querySelectorAll('div[aria-label]'),
        ];
        const names = nameElements.map(fetchName).filter((name) => name);

        function fetchName(nameElement) {
            let attributeValue = nameElement.getAttribute('aria-label');
            let match =
                attributeValue.match(
                    '^Afficher d\'autres actions pour (.+)$'
                ) || [];

            return match[1] || null;
        }

        return names
            .filter((currentValue, currentIndex, elements) => {
                return currentIndex === elements.indexOf(currentValue);
            })
            .sort();
    }

    function displayNameList() {
        const overlayElement = document.createElement('div');
        const headerElement = document.createElement('div');
        const titleElement = document.createElement('div');
        const helpElement = document.createElement('div');
        const refreshNameListButtonElement = document.createElement('button');

        var isDown = false;
        var offset = [0,0];

        // Overlay
        overlayElement.classList.add('whoHasTalkedNameList');
        overlayElement.style.position = 'absolute';
        overlayElement.style.backgroundColor = '#e8eaed';
        overlayElement.style.boxShadow = '0 1px 2px 0 rgba(60,64,67,.30), 0 1px 3px 1px rgba(60,64,67,.15)';
        overlayElement.style.padding = '1em';
        overlayElement.style.top = '4px';
        overlayElement.style.left = '4px';
        overlayElement.style.zIndex = '999';
        overlayElement.style.fontSize = '.85em';
        overlayElement.style.borderRadius = '.85em';

        overlayElement.addEventListener('dblclick', function (event) {
            this.remove();
        });
        overlayElement.addEventListener('mousedown', function (event) {
            if (event.button === 0) {
                isDown=true;
                offset = [
                    overlayElement.offsetLeft - event.clientX,
                    overlayElement.offsetTop - event.clientY
                ];
            }
        });
        document.addEventListener('mouseup', function (event) {
            isDown=false;
        });
        document.addEventListener('mousemove', function (event) {
            event.preventDefault();
            if (isDown) {
                overlayElement.style.left = (event.clientX + offset[0]) + 'px';
                overlayElement.style.top = (event.clientY + offset[1]) + 'px';
            }
        });

        // Header
        titleElement.textContent = 'Who has talked?';
        titleElement.style.fontSize = '1.5em';
        titleElement.style.padding = '0.5em';

        helpElement.textContent = 'Click on a name to remove it from the list.';
        helpElement.style.fontSize = '0.75em';
        helpElement.style.padding = '0.5em';
        helpElement.style.color = '#3c4043';

        refreshNameListButtonElement.textContent = 'Refresh list';

        refreshNameListButtonElement.style.border = 'none';
        refreshNameListButtonElement.style.borderRadius = '1em';
        refreshNameListButtonElement.style.padding = '.5em 1em';
        refreshNameListButtonElement.style.boxShadow = '0 1px 2px 0 rgba(60,64,67,.30), 0 1px 3px 1px rgba(60,64,67,.15)';
        refreshNameListButtonElement.style.backgroundColor = '#00796b';
        refreshNameListButtonElement.style.color = '#fff';
        refreshNameListButtonElement.style.fontWeight = 'bold';

        headerElement.appendChild(titleElement);
        headerElement.appendChild(helpElement);
        headerElement.appendChild(refreshNameListButtonElement);
        overlayElement.appendChild(headerElement);

        // Name list
        const nameListElement = document.createElement('ul');

        overlayElement.appendChild(nameListElement);

        refreshNameListButtonElement.addEventListener('click', function () {
            let names = fetchNamesFromUserList();

            if (0 === names.length) {
                console.log(
                    'Fetching names from main window. Open user panel to get the full list of participants.'
                );
                names = fetchVisibleNames();
            }

            console.log(names.join('\n'));
            refreshNameList(nameListElement, names);
        });

        document.body.appendChild(overlayElement);
    }

    function refreshNameList(nameListElement, names) {
        nameListElement.innerHTML = '';
        names.map(function (name) {
            nameListElement.appendChild(createNameElement(name));
        });
    }

    function createNameElement(name) {
        const nameElement = document.createElement('li');

        nameElement.textContent = name;
        nameElement.style.margin = '0.5em';
        nameElement.style.cursor = 'pointer';
        nameElement.addEventListener('click', function () {
            if (this.classList.contains('has-talked')) {
                this.classList.remove('has-talked');
                this.style.color = 'black';
                this.style.textDecoration = 'none';
                return;
            }
            this.classList.add('has-talked');
            this.style.color = 'grey';
            this.style.textDecoration = 'line-through';
        });

        return nameElement;
    }
})();

Thanks Yann!