Total Blocking TIme is a Pagespeed metric that may have the same end of TTI(Time to Interactive), which was removed as of Lighthouse 10.0.
You may ask why; the metric has almost no validity on field data. For example, the URL youtube.com fails on Pagespeed mostly because of TBT, but on field data in the similar metric FID it passes, and even in the experimental and new metric INTP it scores in the yellow, meaning it needs just improvement.
If your Wordpress site’s main need is to capture leads using a chat plugin, and it is causing the TBT, you should not care, or maybe find a faster plugin. If your Wordpress main feature uses Javascript, and the JS core file is causing the TBT, you may not care, or just improve the file loading.
TBT may be used to warn you about potential problematic files.
Also, if you are using Wordpress, it may be unlikely you have full ownership of all the Javascript that loads, with that in mind, it’s better to optimize the loading of files, instead of the files themselves.
How to Improve TBT in Wordpress
Use Wp Meteor or Wp Rocket to delay or defer files that are causing TBT. Note that not every file is compatible with this approach, and your plugin may break its functionalities.
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