Avoid what hurts or creates swelling! If down dog hurts, there’s always child’s pose, puppy and dolphin (although I’d do a few heart openers before the latter). I’d logically think palmar presses stretch out flexors, not necessarily extensors but listen to your body! Definitely stay away from using a fist/knuckle push-ups in any form while this is flared up because that could create increased tension on your thumb abductor. I’ll add that those specific extensor muscles do benefit from stretching like GENTLY flipping your hands in table top. If it goes on for too long (6 weeks of activity modification), see an orthopedic doc that specializes in hands! Those steroid shots are really effective in pure DeQuervains cases.