Why does javascript not react to modifications in the HTML code?

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Javascript is executed or interpreted by the browser after the HTML code is loaded and rendered on the page. Therefore, if the HTML code is modified dynamically, the changes will not affect the currently executed Javascript code. To make Javascript react to modifications in the HTML code, the code needs to be executed again after the modifications are made. This can be done by adding event listeners or using Javascript frameworks that handle changes in the HTML code automatically.