I know the T dropdown gives us options to increase or decrease, but if I copy-paste something in a big font, like a headline, clicking “100% (default)” does nothing. Somehow, that’s the new default size.

Young tourists deported from US after not planning their trip well enough

I can only drop that to 80% size

Young tourists deported from US after not planning their trip well enough

If I copy-paste again, it still knows that’s 80%. The only way to get it normal is to paste it where I’ve already typed, so it uses the existing setting Young tourists deported from US after not planning their trip well enough

Does anyone know a simpler way? (edit: and now 80% is the new default, so “default size” basically means nothing)

It looks like what you copied is a heading. Under the ¶ menu, try changing it from "Heading 1" down to "Paragraph".