The FID is almost tied to the TBT (Total Blocking Time), one of the Lighthouse performances. So, the TBT overall performance score is 25%, you will be able to understand how your PageSpeed Insights score will be affected by JS Scripts.
- Total CPU Time
- Script Evaluation
- Script Parse
When testing your WordPress website performance in the GTmetrix shows you a very similar result.
- Delay JS and Remove Unused JS
- Defer JS
- Minify JS
Below are several plugins that can help you Delay JS and Remove Unused JS, Defer JS and Minify JS.
Delay JS and Remove Unused JS using the WP Rocket:
If you’re using the WP Rocket plugin for your website, you can Delay JS and Remove Unused JS very easy way, Look at the attached.
Defer JS with WP Rocket plugin:
Below an example of the defer JS attribute:
I recommend you Asset CleanUp plugin, you can use the Asset CleanUp pro version. Also, You can take remove these issues using the WP Rocket plugin. So, Check the attached.
Minify JS Using WP Rocket:
The WP Rocket plugin offers you a simple way to minify JS files. First, Go to the WP Rocket Setting and open the File Optimization tab, and activate the Minify JS files.
Also, you can use another plugin. Like: Autoptimize, W3 Total Cache, WP Fastest Cache plugin, etc.
Check this article, the complete guide: Speed Up WordPress Website.
- Use a static image instead of a slider.
- Avoid overusing widgets such as social networks or third-party scripts in your sidebar or the Footer.