ExperimentsSite speed
The biggest speed win was hidden icon and font files that my caching plugin did not touch
In short
A page-builder widget loaded a full icon font and web fonts directly. Making them non-blocking took the mobile score from 81 to 98 on a test address that skipped the cache.
What I did
I worked on a roofing contractor's mobile speed. First I removed plugin files that pages did not use. That only moved largest contentful paint from 4.1 to 3.9 seconds. Then I found that a custom header widget loaded a full icon font, about 295 KB of font files, and web fonts directly in its HTML. Because they were not added the normal WordPress way, the caching plugin did not optimise them. I made them load without blocking the page, and I also changed the caching plugin's own settings along the way.
Where
A roofing contractor website, May 2026
What changed
On a test address that skipped the page cache, largest contentful paint dropped to 2.3 seconds and first contentful paint from 2.9 to 1.5 seconds. The mobile score went from 81 to 98. Live score after the cache purge: not measured.
Did it work
It worked
What you should do
Search your page source for font and icon files that load in widgets or custom HTML. Your optimisation plugin may not touch them.
How long it took
About a day
A render-blocking file is one the browser must download before it can show the page. Icon fonts and web fonts are common examples.
Why it matters
Here the caching plugin did not touch the icon and font files that a page-builder widget wrote straight into the HTML from outside servers. On this site, those hidden files were the main reason the page was slow.
How to check your own site
- View your page source and search for font, icon and fonts.googleapis.
- In PageSpeed Insights, check the render-blocking list for files that do not come from your theme or plugins.
At a glance
ResultIt worked
Effort to copyAbout a day
Type of businessHome services and trades
SubjectSite speed
81 to 98mobile speed score, on a test address that skipped the cache
4.1 to 2.3 slargest contentful paint, same test address
0.2 sgained from plugin cleanup alone
| Status | Done |
|---|---|
| Hypothesis | Making the hidden icon and font files non-blocking will cut load time more than plugin settings did. |
| Measured by | Mobile PageSpeed score, LCP and FCP |
What this changed in how I work
The usual plugin settings gave small wins. The big win was in code the plugins did not handle. I now search the raw page for hidden files first.
End of Lab entry No. 040