FWIW, Glowforge support responded to the previous post with:
Hello - those gold diamonds are used to highlight the features that are part of Glowforge Premium. I’m afraid we are unable to remove them."
I’m a developer, so this tells me that either Glowforge has the world’s worst developers, or this isn’t the truth. And, since I know the Glowforge developers are pretty good, it isn’t the truth. They absolutely can remove all of the Premium features if you’re not getting Premium. Somebody has apparently made the decision that they want to have annoying clutter (aka UI pollution) for all the people who aren’t paying $50 per month. This is a very bad decision — people react negatively, not positively, to what is effectively badgering — and I hope they reverse it.
Having the gold diamonds during the free trial period makes sense. It tells new customers which parts of the interface are part of Premium and which are included in the free service. But, once your trial is over and you haven’t paid, both the widgets and the gold diamonds should go away.
I agree on leaving the GO PREMIUM button. It is a relatively non-annoying way to promote the upgrade for those who might find it useful. It doesn’t feel like clutter or pollution.