Locate the YouTube video to embed in a text box.
Select Share.
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The YouTube sharing panel will appear.
Select Embed.
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The YouTube video embed code will appear in the text field.
Position the cursor.
Position your cursor where to embed the video, then paste the YouTube embed code (Ctrl + V for PC or Command + V for Mac).
Select Source again.
This returns the text box display to normal editing mode. The embedded YouTube video will display as a box marked IFRAME. When the item using the text box is posted or saved, the embedded YouTube video will display.
Select Save.
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Select Save to view the embedded YouTube video.