Phone doesn't mount on laptop

[lsitongia]

When Jump Drive is running on the phone, plugging it into my Manjaro Plasma laptop via USB mounts the phone as a storage device. On the laptop, I can see the phone's eMMC and the SD card. But, when Manjaro Plasma mobile is flashed to the phone's eMMC and up and running, plugging it in doesn't mount anything. Nothing is logged on the laptop when the USB is plugged in and removed. I'm using the same red USB cable that came with the phone in both cases, Jump Drive and running system. What is different?

How do I get the phone to mount as a storage device on my laptop?

I'm running Manjaro Plasma mobile beta2.

Thanks!