When I was running Gentoo, I wanted to replace the GNOME foot that appeared on the dropdown menu with a Gentoo-fish-in-a-wizard-hat icon.
I found documentation suggesting that the icon shown on the menu was set in a certain configuration file, and changed that file.
This meant that, when I was using the normal UI to customize the GNOME topbar, the icon associated with that menu, in the GUI, was the fish-wizard icon. But it did not change the icon displayed in the menu itself.
I always resented that. I still don't like the concept of hiding configuration lest the user change it.
Turned out that didn't work, because there was an additional sanity check that halted the boot process if the "LI" bytes were corrupted.
Of course I put through and was a happy user of PIPO for some years, until Grub came along.
[1] https://en.m.wikipedia.org/wiki/Pipo_de_Clown