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The Embed module will, by default, supply a button icon for you if you don't have one. The downside is, it's simply the letter E.

If you would like something a little more symbolic, you'll want to create an icon graphic with a 1:1 aspect ratio prior to starting this tutorial.

Click on an image to make it bigger.
D8 Embed Buttons - Create - Navigation

1. Navigate to Embed Buttons

Go to Admin Menu > Configuration > Content Authoring > Text Editor Embed Buttons.

D8 Embed Buttons - Create - Click Add Embed Button

2. Initialize Embed Button

From the Embed Buttons screen, click the Add Embed Button button.

D8 Embed Buttons - Create - Name Embed Button

3. Give the Button a Name

Label text field = enter your button name.

D8 Embed Buttons - Create - Select Entity Type

4. Select Entity Type

Entity Type select field = select Media.

Once you select Media, all the Media entity type configuration settings will appear.

Allowed Entity Embed Display Plugins options (these are actually the View Modes that we created earlier)

  • Thumbnail
  • 150 Wide Scaled
  • 300 Wide Scaled
  • 450 Wide Scaled
  • Colorbox
  • Download
  • Original
  • Thumbnail
D8 Embed Buttons - Create - Select Entity Browser

5. Select Entity Browser

Entity Browser select field = WYSIWYG Media Browser (this is the Entity Browser that we created earlier).

D8 Embed Buttons - Create - Add Button Icon

6. Add Icon

Button Icon upload field = if you have a custom icon graphic, upload it here.

Click the Save button.

D8 Embed Buttons - Create - Embed Button Created

7. Completed Embed Button

You will be redirected back to the Embed Buttons main screen.

Your new button will appear in the list.