Refreshing the Ubuntu Desktop Installer

@Wimpress This is great news. Since the switch to Flutter might impact the flavo(u)rs and remixes out there, I have a few questions about ubuntu-desktop-installer (the new installer):

  • Will it allow custom theming for the distributions? (other than official flavo(u)rs, like remixes and derivatives like Linux Mint and non-Ubuntu-based distributions, as it will then be a viable cross-distribution alternative to Calamares)
  • Will it operate properly on QT desktops? (there are many UI glitches that occur when using applications that use the Flutter toolkit on QT desktops like KDE)
  • Will it allow custom slideshows? (as it is possible with Ubiquity)