In 1.3.12, Savitar no longer successfully intensifies text colors. If, under World Settings/Appearance, I select "automatically intensify the text color", intense default/plain now shows up the same as regular default/plain, rather than as the color I've set for Intense White (which is what it used to show in .11). If I select 'use this text color for intense' via that settings box, it then applies that blanket color choice appropriately.

To correct: the old color selection in that case wasn't "intense white." Nor was it "dim white," or any other color I'd selected there. Perhaps the effect upon which I'd been relying was a bug

Yes, the original factory default colors were set rather poorly on versions of Savitar prior to 1.3.12. If you set the colors yourself, or, hit the "Defaults" button in the ANSI color dialog in 1.3.12, you'll get decent intense color behavior now.