With Chrome or Safari browsers, Drag & drop of an image does not work on html fields in Service Portal.

1. Log in any instance
2. Create an html variable and add it to a catalog item
3. Open the catalog item in the service portal
4. Drag and drop an image into the html field displayed for the variable

The following behaviours are observed:
- In Firefox the image is added into the HTML field.
- In Chrome the image is not added and the browser redirects to a full screen image view.
- In Safari the image sometimes gets added as icon to the HTML field, sometimes nothing happens, and sometimes the browser redirects again to the full screen image view.

This issue has been identified as a product enhancement. Not all platform features are implemented in Service Portal, and drag and drop for images was not part of the initial design for HTML fields in Service Portal. 
In a future release, we plan to abandon the Service Portal specific implementation of the TinyMCE HTML Editor, and to use a new platform UI version, so to allow full HTML field capabilities in the new Service Portal.
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