At the third page from the "Event-Actions" (where you have "add Text", "Conditions", "Variables",...) there should be an Event-Action called "Plugin Command". Click on that and write / copy&paste the needed command. Hope you understand what I mean, else just look on google after "rpg maker mv plugin commands".

Where do I actually input this plugin command?

░░▄ ▀▄▄▀▄░░░░░░░░░ This is Toby.
░█░░░░░░░░▀▄░░░░░░▄░Toby wants to take over Steam.
█░░▀░░▀░░░░░▀▄▄░░█░█He needs your help.
█░▄░█▀░▄░░░░░░░▀▀░░█Copy/paste Toby to help him.
█░░▀▀▀▀░░░░░░░░░░░░█If not, he will use the Legendary Artifact's power. On you.
█░░░░░░░░░░░░░░░░░░█
█░░░░░░░░░░░░░░░░░░█
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░█░▄▀█░▄▀░░█░▄▀█░▄▀░ :tobdog:

Thanks, I have updated the plugin. You have more control now, hope that helps. ^^
PS: Window-Size / Message-Box, etc. will be not affected / scaled, like before (version 1.0).

This plugin is good, but I was wondering if there is a way to have the font size in the plugin affect only the text in the message window? When I change the font size it invariably changes the size of the text in the menus as well.
I hope I'm not bothering you