[CentOS] Annoying shortcut

For at least this year, I'm finding that whether I'm in LibreOffice, or Thunderbird, or Firefox, if I do *something*, and I haven't identified what, backspace will delete the entire word, though I haven't hit ctrl-bkspc. In system settings, it should only be the ctrl-bkspc. Has anyone else see

[CentOS] I get "bad shim signature" booting with Secure Boot enabled

Hi, If I enable Secure Boot in my UEFI I get this error (just after selecting Centos from the grub menu) grub-core/kern/efi/sb.c:151: bad shim signature grub-core/loader/i386/efi/linux.c:208: you need to load the kernel first Can someone explain to me why I get this, please? And what can I do to