icomplete-vertical VS live-completions

You can display icomplete/fido vertically if you like that better with (setq icomplete-separator "\n") or with https://github.com/oantolin/icomplete-vertical

I don't use icomplete nor vertico most of the time, but I am very familiar with them. I've tried lots of completion UIs: default completion, ido (with ido-completing-read to get it everywhere), icomplete, vertico, selectrum, helm, ivy; and I've written several myself: icomplete-vertical, live-completions, grille, embark-collections-completions.

Helm commands only work in Helm. Ivy and Counsel commands only work in Ivy. Consult commands work in Selectrum, Vertico, Icomplete Vertical, and maybe some other interfaces. That's all I meant. Of course, that only matters if you don't wish to use Helm or Ivy.

Consult supports asynchronous candidate sources now! This allows to implement grep and find commands which update the candidate lists while you type. Consult is made to work well with the default completion system, Selectrum and Icomplete-vertical.

I don't use icomplete nor vertico most of the time, but I am very familiar with them. I've tried lots of completion UIs: default completion, ido (with ido-completing-read to get it everywhere), icomplete, vertico, selectrum, helm, ivy; and I've written several myself: icomplete-vertical, live-completions, grille, embark-collections-completions.

I too am guilty of once writing a package that updates the *Completions* buffer as you type: live-completions. My package didn't have a way to move the "currently selected" completion from the minibuffer (because I didn't mind switching to the completions buffer for that). Recently u/protesilaos also wrote his own version, in prot-minibuffer.el. I'm sure there are many other examples.