DOM navigation error? getElementsByTagName error

If you open the developer tool to get the video tag from Naver blogs or cafes and run document.getElementsByTagName('video') or document.querySelectorAll('video') you will find a strange empty array. What's more strange is that if you search <video on the Elements tab with Ctrl+F, once you click the part of the video tag you found and run document.getElementsByTagName('video') again, you will return the normally. What the hell is the problem??


javascript
dom
element
					
					

	


		
	

	
		2022-09-20 22:12



			

			
			1 Answers


	
		
I answer myself... This is because the Naver video uses the iframe tag.
document.querySelectorAll('iframe').forEach(item =>
  item.contentWindow.document.body.querySelectorAll('video');
)


		
		
			

				

					
				

				
					2022-09-20 22:12
				
			
		
	
			
			If you have any answers or tips



		

	
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