I too have MCU1.
Browser is almost a lost cause right now...
It had so much promise as a window to the world, a portal of which any capability can be added to the car with a wonderfully large screen. I used to routinely run Tesla wind, dark sky weather radar and Waze. Now, the browser just doesn’t work. It may, may sometimes load something if the sketch pad is up, but it locks up so much that I don’t bother anymore.
I held out hope that Tesla would fix it, but given MCU 1 cars are not made anymore and there are fewer of them in the road each day, I don’t see it happening.
Our best hope is that they would allow MCU1-MCU2 retrofit, but I don’t hold too much hope for similar reasons.
Maybe get a suction cut case for my phone or iPad and stick it up there.