It says it in your screenshot, run rofi -list-keybindings. Then probably, you will have this lines coming from the defaults: kb-mode-complete - Control l.

Please re-open if it persists

It says it in your screenshot, run rofi -list-keybindings. Then probably, you will have this lines coming from the defaults: kb-mode-complete - Control l.

rofi -list-keybindings just displays all keybindings that are available. It does not provide any information on where the bindings are set. As far as I have found from the rofi documentation, there is a system config file in /etc/rofi.rasi. However in my case that file is empty.

So the only file where keybindings are set is ~/.config/rofi/config.rasi and that file has no other bindings set for kb-mode-complete

I moved all custom keybindings to /etc/rofi.rasi as follows:

configuration {
  kb-row-up:                      "Up,Control k,Shift Tab,Shift ISO_Left_Tab";
  kb-row-down:                    "Down,Control j";
  kb-accept-entry:                "Control m,Return,KP_Enter";
  kb-remove-to-eol:               "Control Shift e";
  kb-mode-next:                   "Shift Right,Control Tab,Control l";
  kb-mode-previous:               "Shift Left,Control Shift Tab,Control h";
  kb-remove-char-back:            "BackSpace";
}

The issue still persists.

I somehow fixed this problem but I don't understand how it works. First i checked rofi -help to see all the keybinds, in there the kb-mode-complete was listed as a default binding not a rasi file binding. Therefore, it doesn't make sense to disallow any other command using the same shortcut key.

First I tried to bind kb-mode-complete to other shortcuts like Control u or Control x that resulted in the same error. I tried to unbind it as well by doing kb-mode-complete: "" and that also didn't work.

I finally tried to bind kb-mode-complete to Control 8 and that somehow worked. If anyone has any insight on what the problem could be please share here. Thank you.