It is not possible to upload custom SVG title/logo/favicon or background image to Plesk: The SVG file cannot be uploaded: Suspicious atribute

Symptoms

• Attempt to upload custom SVG file to Plesk in Tools & Settings > Branding (as in (How to change Plesk title, logo, favicon and background image for login screen article) fails with error message (error may vary):

The SVG file /opt/psa/tmp/fup0WvChW cannot be uploaded: Suspicious attribute 'atribute-name' (Line: 3) Suspicious node 'svg'

The SVG file /usr/local/psa/tmp/fupzdEvEg cannot be uploaded: Suspicious node '#comment' (Line: 2)about accept action align alt autocomplete background bgcolor border cellpadding cellspacing checked cite class ...

Cause

SVG file contains suspicious attributes.

Resolution

Delete suspicious attributes using Notepad++ or use SVG Image optimizer (for example, Optimize SVG Images Online).