Bookmarklet to automagically create and copy a watch to the clipboard based on the selected text

watch-creation-bookmarklet.js

javascript:(async function () {
    /* Based on this bookmarklet by Makyen: https://chat.stackexchange.com/transcript/11540?m=55327802
     * which is based on this code by Tim Down to get selected text: https://stackoverflow.com/a/5379408/208273
     */
    var text = "";
    const activeEl = document.activeElement;
    const activeElTagName = activeEl ? activeEl.tagName.toLowerCase() : null;
    if ((activeElTagName == "textarea" || activeElTagName == "input") && /^(?:text|textarea|search|password|tel|url)$/i.test(activeEl.type) && (typeof activeEl.selectionStart == "number")) {
        text = activeEl.value.slice(activeEl.selectionStart, activeEl.selectionEnd);
    } else if (window.getSelection) {
        text = window.getSelection().toString();
    }
    text = text.toLowerCase().trim();
    const textRegex = text.replaceAll(".", "\\.").replaceAll(" ", "[\\W_]*+");

    try {
        await navigator.clipboard.writeText(`!!/watch ${textRegex}`);
    } catch (err) { 
        alert('Failed to copy watch text. ', err);
        return;
    }

    const plainSearch = encodeURIComponent(`"${text}"`);
    const urlSearch = encodeURIComponent(`url:"${text}"`);
    const codeSearch = encodeURIComponent(`code:"${text}"`);

    /* Simpler (and faster) bookending than Makyen's because we will never include ^ or $ in the regex */
    const searchTerm = encodeURIComponent(`\\b(?s:${textRegex})\\b`);
    const searchTitle = `&title_is_regex=1&title=${searchTerm}`;
    const searchBody = `&body_is_regex=1&body=${searchTerm}`;
    const searchUsername = `&username_is_regex=1&username=${searchTerm}`;

    /* Tabs open in reverse order of window calls. Calls are ordered (approximately) from slowest to fastest for ease of tabbing through */
    window.open(`https://metasmoke.erwaysoftware.com/search?utf8=%E2%9C%93${searchTitle}${searchBody}${searchUsername}&or_search=1`);
    window.open(`https://stackexchange.com/search?q=${urlSearch}`);
    window.open(`https://stackexchange.com/search?q=${codeSearch}`);
    window.open(`https://stackexchange.com/search?q=${plainSearch}`);
})();