The JavaScript delay feature, which is available in almost all WordPress plugins today, was available in only 3 plugins before 2020. From where? In the optimization industry, there was no approach adopted and known by the majority in the form of JavaScript delay. For years before 2020, this method was more or less talked about in foreign optimization communities.

The field of optimization is a very wide field.WordPress Speed OptimizationIt is not just a WordPress specific area, but also php, js, asp.net, python etc. It can be done on sites prepared with any programming language or ready-made content management system (cms such as opencart, drupal, magento, etc.). It is a very wide field, so it is not possible for us to say who discovered and spread this tactic in speed optimization. However, as someone who has been following the developments and systems in the field of programming and Linux in Turkey and globally since 2015, we would like to give you the answer to the main question with the evidence on the subject: "Who first started this javascript delay trend in WordPress?"

Since 2017-2018, wordpress plugins called swift performance and pagespeed ninja were the only two regularly developed plugins that offered the "javascript delay" feature in WordPress with different variations (google analytics delay, adsense delay, etc.). They still offer it and they have improved themselves even more. But these two plugins were not popular globally until 2020. It is still not popular in Türkiye. In Türkiye, until 2020, the number of people who knew that there was an effective optimization strategy called js delay and used these two plugins effectively in optimization was less than 10. Over the years, it became very popular, first globally and then in Türkiye. In 2020-2021, WordPress plugin developers quickly added the js delay feature to their plugins and continued to develop it. In 2022-2023, there is no plugin left without a js delay feature. In fact, in 2021, the litespeed cache plugin developed a feature called guest mode, which deceives bots, that is, it provides high scores in testing tools by only showing bots the not fully loaded version of the page. Unfortunately, most people who optimize WordPress, especially forums, use this trick and it does not actually speed up the sites. It's just that the test vehicles score seems high. But this is a separate topic, so I won't go into it. To sum up our words, these two plugins are the first to practically implement/code JavaScript delay in WordPress and offer it publicly to users:

Swift Performance and PageSpeed Ninja

Swift Performance:https://swiftperformance.io/

PageSpeed Ninja:https://pagespeed.ninja/

The PageSpeed Ninja plugin was in beta until a few months ago in 2023, but it has just moved to the stable version. The Swift Performance plugin was released in a stable version for many years. However, the main add-on (swift performance) project was terminated with support for it discontinued in 2024. Then, it was offered in beta phase as a new plugin called Swift Performance AI in 2022, with features that are not available in any other optimization plugin in WordPress, including "artificial intelligence", "dynamic cache" and "admin panel acceleration".

See: (update records of relevant plugins - evidence of the year and month in which js delay features were added):

https://wordpress.org/plugins/psn-pagespeed-ninja/#developers

https://docs.swiftperformance.io/changelog