Made a few failed attempts at trying Manjara, finally got it installed and all working ok. But I have done this as a dual boot along with Ubuntu Studio 18.04. Each distro is installed on its own M.2 (256Gb) drive and I think I have screwed up the boot loader (grub). Initially, I used the Manjaro grub to boot from and all worked ok but I think that when I was in Ubuntu Studio, I also did an 'update-grub' (was showing someone how to sort grub) and now, only the Ubuntu Studio grub shows at boot and the Manjaro boot options do not work and I get a black screen if I choose them.
I can get into Manjaro by choosing that boot option in the bios, but that is not ideal and I have now lost the option to boot Manjaro with a different kernel, I have spent quite a bit of time trying to sort out grub and am getting nowhere.
Got to the point where I may as well start again but that will take many hours of config for both distros. Is there a way to undo/fix the grub on both distros? Would prefer Manjaro grub (looks nicer) but if I could get either to work properly it would be a bonus..