How to change icon size larger than 100px or custom?

Folks, I’m a bit frustrated. @steviemc posted his question in March 2018 and got no answer. I came along with my previous post in June 2019 and got no answer. It’s now the end of Feb. 2020 and STILL NO ANSWER. Come on, folks!

Yes, my Project Settings are set to “inherit” as shown here:

But putting a class on my icon and setting the font size does NOTHING. Why? What’s the fix or workaround? (That’s been my question since June 2019!)

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