White pests on Hydrangea

Hi, I’m hoping someone can help identify the “white blobs” that are invading my hydrangea. I’ve had it about 25 years and have never seen anything like these blobs before. They are about 5mm long and have a marshmallow, sticky like consistency. They appear to be mailnly on the older woody stems and my hydrangea doesn’t seem to suffering I’ll effects as yet...