fullscreen.admin.css

.ckeditor5-toolbar-button-fullscreen {
  background-image: url(../icons/fullscreen-enter.svg);
}

File

View on git.drupalcode.org

core/modules/ckeditor5/css/fullscreen.admin.css

View source 
  1. .ckeditor5-toolbar-button-fullscreen {

  2.   background-image: url(../icons/fullscreen-enter.svg);

  3. }

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