Daniel Mahaffy

The “All-in-One Event Calendar” by Time.ly works great, but uses dynamic javascript. 
This plugin creates a static version of the javascript that can be cached by 
the browser.
I have tested this plugin with versions 2.1.9 and 2.2.0 of the event calendar plugin. 
It may work with future releases, but use it at your own risk.
This plugin only uses the static javascript on the frontend. If a user is 
logged in, the original dynamic script will be used. As far as I can tell 
caching the javascript does not interfere with the plugin’s functionality, but 
there may be features of the event calendar that do not work with this plugin.

Fix Event Calendar Caching

This plugin makes the All-in-One Event Calendar's javascript cacheable to improve page load speed.

WordPress.org

This plugin offloads JavaScript execution to a Web Worker, improving performance by freeing up the main thread. This should translate into improved <a href="https://web.dev/articles/inp" rel="nofollow ugc">Interaction to Next Paint</a> (INP) scores.
⚠ This functionality is experimental, and it is now <a href="https://github.com/WordPress/performance/issues/2284" rel="nofollow ugc">intended to be sunset</a>. ⚠
In order to opt in a script to be loaded in a worker, simply add <code>worker</code> script data to a registered script. For example, 
if you have a script registered with the handle of <code>foo</code>, opt-in to offload it to a web worker by doing:
<pre><code>wp_script_add_data( 'foo', 'worker', true );
</code></pre>
Unlike with the script loading strategies (async/defer), any inline before/after scripts associated with the worker-offloaded registered script will also be offloaded to the worker, whereas with the script strategies an inline after script would block the script from being delayed.
Otherwise, the plugin currently ships with built-in integrations to offload Google Analytics to a web worker for the following plugin:
<ul>
<li><a href="https://wordpress.org/plugins/seo-by-rank-math/" rel="ugc">Rank Math SEO</a></li>
<li><a href="https://wordpress.org/plugins/google-site-kit/" rel="ugc">Site Kit by Google</a></li>
<li><a href="https://wordpress.org/plugins/woocommerce/" rel="ugc">WooCommerce</a></li>
</ul>
Please monitor your analytics once activating to ensure all the expected events are being logged. At the same time, monitor your INP scores to check for improvement.
This plugin relies on the <a href="https://partytown.builder.io/" rel="nofollow ugc">Partytown 🎉</a> library by Builder.io, released under the MIT license. This library is in beta and there are quite a few <a href="https://github.com/BuilderIO/partytown/issues?q=is%3Aopen+is%3Aissue+label%3Abug" rel="nofollow ugc">open bugs</a>.
The <a href="https://partytown.builder.io/configuration" rel="nofollow ugc">Partytown configuration</a> can be modified via the <code>plwwo_configuration</code> filter. For example:
<pre><code><?php
add_filter( 'plwwo_configuration', function ( $config ) {
 $config['mainWindowAccessors'][] = 'wp'; // Make the wp global available in the worker (e.g. wp.i18n and wp.hooks).
 return $config;
} );
</code></pre>
However, not all of the configuration options can be serialized to JSON in this way, for example the <code>resolveUrl</code> configuration is a function. To specify this, you can add an inline script as follows.
<pre><code><?php
add_action(
 'wp_enqueue_scripts',
 function () {
 wp_add_inline_script(
 'web-worker-offloading',
 <<<JS
 window.partytown = {
 ...(window.partytown || {}),
 resolveUrl: (url, location, type) => {
 if (type === 'script') {
 const proxyUrl = new URL('https://my-reverse-proxy.example.com/');
 proxyUrl.searchParams.append('url', url.href);
 return proxyUrl;
 }
 return url;
 },
 };
 JS,
 'before'
 );
 }
);
</code></pre>
There are also many configuration options which are not documented, so refer to the <a href="https://github.com/BuilderIO/partytown/blob/b292a14047a0c12ca05ba97df1833935d42fdb66/src/lib/types.ts#L393-L548" rel="nofollow ugc">TypeScript definitions</a>.

Web Worker Offloading

Offloads select JavaScript execution to a Web Worker to reduce work on the main thread and improve the Interaction to Next Paint (INP) metric.

Fix Event Calendar Caching vs Web Worker Offloading