HTML comments are shown with a generic "notice" icon, however as such comments are part of the user generated content and (usually) actual human generated "comments" it would make more sense to use the speech bubble icon used elsewhere. A speech bubble icon with a ! also exists in Echo and so this can just be copied over to VE.
A speech bubble better highlights this as a message from other editors, rather than a system-generated error/notice that needs to be "fixed" or otherwise addressed.
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