With upcoming changes to scripts used to produce all installation media, the bootloaders used to boot will change.
Previously we used ISOLINUX with GFXBOOT when booting in BIOS mode. Grub2 when booting in UEFI mode.
With the above change, only GRUB2 will be used to boot the installation media.
It means that installation experience will be the same, if one boots CD-ROM, USB, under either UEFI or BIOS. The same grub.cfg will be used in all cases, and the same menu will be shown and the same kernel cmdline options will be used.
This will change how some things appear, however the installer will now behave a lot closer to how the installed systems boot.
There are no changes to plymouth, plymouth themes, actual installers.
All existing boot targets will continue to be supported. However, if you notice that Groovy installers stop booting after the above mentioned changes land, then please respond to this thread with details of how the installation media is prepared, how it is booted, and on which hardware configuration.
This change affects all flavours.