How do I embed a YouTube video in a text box?
Locate the Youtube video you would like to embed in a text box.
Click Share.
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This displays the YouTube sharing panel.
Click Embed.
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This displays the YouTube video embed code.
Copy the embed code.
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Copy the YouTube embed code to your computer's clipboard (CTRL-C - PC or COMMAND-C MAC).
Tip: Remove the check mark next to "Show suggested videos when the video finishes"
In the text box, click Source.
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This displays the HTML code for the text box.
Position the cursor.
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Position your cursor where you would like the video embedded, then paste the YouTube embed code (CTRL-V - PC or COMMAND-V - MAC).
Click Source again.
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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, it displays the embedded YouTube video.