Tampermonkey script that extracts hi-res MP4 movie file URLs from tweet permalink page.

twitter_video_extractor.user.js

// ==UserScript==
// @name         Twitter video extractor
// @namespace    https://dislife.com/
// @version      0.0.3
// @description  Extract hi-res MP4 movie file URLs from tweet permalink page
// @author       mizuki@mozurin.com
// @match        https://twitter.com/*/status/*
// @grant        none
// @run-at       document-body
// ==/UserScript==

(function() {
    'use strict';

    const injectCode = function ()
    {
        const APP_NAME = 'Twitter video extractor';
        const APP_ID = 'TwitterVideoExtractor';
        const MENU_TEXT = 'Extract video file URLs';
        const NOTFOUND_TEXT = 'Video files are not found.';

        function log(msg)
        {
            console.log('[' + APP_ID + '] ' + msg);
        }


        // video information extractor
        let jsonTree;

        function statusFetched(response)
        {
            jsonTree = (
                typeof response == 'string'?
                JSON.parse(response) : response
            );
        }

        function parseAndShowList()
        {
            if (!jsonTree) {
                log('Tweet JSON tree not fetched. Updating the script update might be required.');

                return;
            }

            if (document.getElementById(APP_ID)) {
                log('Video list box is already open.');

                return;
            }

            const foundVideos = [];

            for (const tweet of Object.values(jsonTree.globalObjects.tweets)) {
                if (!tweet.extended_entities || !tweet.extended_entities.media) {
                    continue;
                }

                for (const media of tweet.extended_entities.media) {
                    if (media.type != 'video') {
                        continue;
                    }

                    foundVideos.push(
                        {
                            thumbnail: media.media_url_https,
                            url: media.video_info.variants.sort(
                                (a, b) => (b.bitrate? b.bitrate : 0) - (a.bitrate? a.bitrate : 0)
                            )[0].url,
                        }
                    );
                }
            }

            // build and show popup
            const parserBox = document.createElement('div');
            let innerSrc = `
                <div id="${APP_ID}" style="position: fixed; left: 3em; right: 3em; top: 3em;
                bottom: 3em; background: white; border: solid gray 1px;">
                    <p style="background: #348; color: white; margin: 0;
                    padding: 0.5em; padding-left: 3em; overflow: hidden; line-height: 3em;">
                        ${APP_NAME}
                        <button type="button" style="float: right; height: 3em;"
                        onclick="document.getElementById('${APP_ID}').remove();">
                            close
                        </button>
                    </p>
            `;

            if (foundVideos.length < 1) {
                innerSrc += `
                    <p style="color: red; font-size: 120%; font-weight: bold; text-align: center;">
                        ${NOTFOUND_TEXT}
                    </p>
                `;
            } else {
                innerSrc += `
                    <div style="overflow: hidden scroll; position: absolute; top: 4em;
                    bottom: 0; width: 100%;">
                `;

                for (const video of foundVideos) {
                    innerSrc += `
                        <a href="${video.url}">
                            <img src="${video.thumbnail}" style="height: 20em; width: auto;
                            margin: 1em; float: left;" />
                        </a>
                    `;
                }

                innerSrc += '</div>';
            }
            innerSrc += '</div>';

            parserBox.innerHTML = innerSrc;
            document.body.appendChild(parserBox.children[0]);
        }


        // append contextmenu
        window.addEventListener(
            'DOMContentLoaded',
            () => {
                const menuId = document.body.getAttribute('contextmenu');
                let menu;

                if (menuId) {
                    menu = document.getElementById(menuId);
                } else {
                    menu = document.createElement('menu');
                    menu.setAttribute('id', 'gmscript-menu');
                    menu.setAttribute('type', 'context');
                    document.body.appendChild(menu);
                    document.body.setAttribute('contextmenu', 'gmscript-menu');
                }

                const item = document.createElement('menuitem');

                item.textContent = MENU_TEXT;
                item.addEventListener('click', parseAndShowList, false);
                menu.appendChild(item);
            },
            false
        );


        // install hook into XMLHttpRequest
        const originXHR = window.XMLHttpRequest;

        window.XMLHttpRequest = function ()
        {
            const xhr = new originXHR(...arguments);
            const originOpen = xhr.open;

            xhr.open = function (method, url)
            {
                if (
                    url.match(/\/api\/2\/timeline\/conversation\/\d+\.json/) ||
                    url.match(/\/api\/2\/rux\.json/)
                ) {
                    this.addEventListener(
                        'readystatechange',
                        function ()
                        {
                            if (this.readyState != XMLHttpRequest.DONE) {
                                return;
                            }

                            statusFetched(this.response);
                        },
                        false
                    );
                }

                return originOpen.apply(this, arguments);
            };

            return xhr;
        };
        Object.setPrototypeOf(window.XMLHttpRequest, originXHR);
    };

    const script = document.createElement('script');
    script.innerHTML = '(' + injectCode.toString() + ')();';
    document.body.appendChild(script);
})();

It doesn't work in my chrome and shows “Refused to execute inline script because it violates the following Content Security Policy directive: "script-src 'self' 'unsafe-inline'”