I am planning to install Manjaro KDE on an external USB SSD drive (SanDisk 500GB). It is meant to run on an HP Spectre Laptop I bought last year that also runs a preinstalled Windows 10 on the internal SSD. The internal SSD should by all means be untouched during the installation. I made a bad experience recently when trying to install Linux Mint on the external SSD. I followed a guide on the Linux Mint forums and did the so-called “UEFI - Unflag/Reflag” method described there. Despite following all steps and specifying the external SSD as the target the stupid Mint installer wrote something on the internal SSD Boot partition and made Windows unbootable, so I had to restore the whole internal SSD from a backup.
I don’t want to screw up my Windows installation again, so are there any precautions I need to take when installing Manjaro? Or is it completely safe to simply select the external SSD as the target for installation?
My plan is to set the BIOS boot priority to 1. USB / 2. internal Drive, so I can decide what system to boot by either plugging in the external SSD before powering on the system or leaving it unattached. Will this work?
Thank you for your help!