Microwave safe glass getting too hot

I've been making hot tea in microwave safe glass measuring/pour cups for many years. Usually Pyrex brand. I put in about 3 cups of water, a tea bag, and set it for 4 minutes, finish, take it out, then let it sit a while. I got a new 4 cup Anchor brand measuring cup, it says microwave safe on the bottom, it looks very similar to the Pyrex ones. I did the same thing I always do. 4 minutes, watched it the whole time, water never comes to a boil except little bubbles around the bag. I went to pick it up by the handle like I always do, and it absolutely burned my fingers in about a half second, I'm getting blisters. I spilled the tea everywhere on my legs and feet, they are red. The empty container handle stayed too hot to touch by bare hand for more than 15 minutes, and it's been a half hour and it's still pretty hot. The container part was cool when empty, the handle was the only part that remained hot. Now, I was probably stupid for not checking the handle, but like I said, I've been doing the same thing for years, really didn't even think about it, I cook many things in those containers, even running some longer than that, I've never had the handle of anything I've had get that hot, especially the entire handle all the way to the end. The Pyrex ones aren't really even warm after that long. Anyone else run into this? I'm not going to use it anymore when the Pyrex ones stay cool enough to use.