[javascript] adding text to an existing text element in javascript via DOM

The reason that appendChild is not a function is because you're executing it on the textContent of your p element.

You instead just need to select the paragraph itself, and then append your new text node to that:

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var paragraph = document.getElementById("p");_x000D_
var text = document.createTextNode("This just got added");_x000D_
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paragraph.appendChild(text);
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<p id="p">This is some text</p>
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However instead, if you like, you can just modify the text itself (rather than adding a new node):

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var paragraph = document.getElementById("p");_x000D_
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paragraph.textContent += "This just got added";
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<p id="p">This is some text</p>
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