Installed 19.04 to sdb drive (internal, but also flash drive as sdc) and it overwrote my /EFI/ubuntu folder on sda.
I changed combo box which never has done anything with UEFI installs, but it does then say during install that it is installing grub to sdb/external.
I clicked on ESP on sda, and said do not use. I clicked on ESP on sdb and said use as ESP.
Several years ago I installed Fedora, just to see grub differences, and it just installed to sdb when I told it to.
So it is Ubuntu's modifications to grub that make it not install to drive you really want.
Installed 19.04 to sdb drive (internal, but also flash drive as sdc) and it overwrote my /EFI/ubuntu folder on sda.
I changed combo box which never has done anything with UEFI installs, but it does then say during install that it is installing grub to sdb/external.
I clicked on ESP on sda, and said do not use. I clicked on ESP on sdb and said use as ESP.
Several years ago I installed Fedora, just to see grub differences, and it just installed to sdb when I told it to.
So it is Ubuntu's modifications to grub that make it not install to drive you really want.