Tampermonkey script run before page load

@run-at 定义注入脚本的时刻。与其他脚本处理程序相反，定义脚本想要运行的第一个可能时刻。这意味着可能会发生使用标签的脚本可能会在文档加载后执行， ...

The (Tampermonkey) content script running at the page needs to get the scripts that should executed from the background page. This is done with some ...

Using the @run-at document-end header causes the script to be injected after the DOMContentLoaded event was dispatched.

Long story short, in Tampermonkey if you set the run-at metadata key to document-start the userscript will begin execution after the entire HTML ...

I have tried many different things (e.g. window.onLoad) but still my script is not effective. Last attempt (failed) is the following: var logo = ...

I've figured it out! Tampermonkey has an experimental setting on advanced config mode for instant script injection, which does what I want.

... run-at, 指定腳本運行時機, document-start：盡快執行 document-body：當body 掛載時執行 document-end：DOMContentLoaded 觸發時執行 document-idle ...

If your script listen to either DOMContentLoaded or page's load event, configure the script to run at document-start using the @run-at metadata ...

addEventListener method. // @run-at document-start. The script will be injected as fast as possible. // @run-at document-body. The script will be injected if ...

That's why Tampermonkey needs to be injected into every page, because only pre-defined content scripts will be executed at document-start for sure. After the ...