Mob Bugs
I was breeding sheep in 1.14.1 and the pre-release of 1.14.2 and there were no particle effects showing, like hearts when they're in 'love mode' and green stars when feeding wheat to lambs. The same thing happened when I tried breeding two dogs I'd tamed, the heart particle effects didn't appear.
Also, when wet dogs sometimes go completely black. I don't know if this was intentional.
Created Issue:
Mob Bugs
I was breeding sheep in 1.14.1 and the pre-release of 1.14.2 and there were no particle effects showing, like hearts when they're in 'love mode' and green stars when feeding wheat to lambs. The same thing happened when I tried breeding two dogs I'd tamed, the heart particle effects didn't appear.
Also, when wet dogs sometimes go completely black. I don't know if this was intentional.

As far as love hearts are concerned, I cannot reproduce. Try checking your particle settings.
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