MicroSD drive support and configuration

Is it possible to use the eMMC for Manjaro and still have a large microSD card in for larger files and as a drive? I understand the boot priority, but is there a way around that? Or is it better to just use an external thumb drive in the dock?

I would like to use the microSD card to store larger files that would always be available on the OS.

Just do not have a bootable OS on the SD card. You might have to go into DIsks app and mount the SD card by hand.

Should mount to /run/media/manjaro/“label of SD”

In the Usage app / storage tab / if mounted you will see aprox. 32Gb + the size of your SD