open-windowed-fullscreen?

[superDuperCyberTechno]

Is it possible to open a window in windowed fullscreen mode? open-windowed-fullscreen doesn't work, so maybe there's other options? Right now I use Mod+F to fire off toggle-windowed-fullscreen, but that's a compromise.

Any plans to implement open-windowed-fullscreen perhaps?

[andsnpl]

Could also see this implemented as open-fullscreen "windowed" or something similar. I could also use this myself, specifically because I open chromium in --app mode for youtube, and I'd like to be able to fullscreen the video within its frame. I'd rather not bind a key for toggle-windowed-fullscreen since I would only use it for this one circumstance.

I haven't tried it yet, but I think I may have claude implement a daemon to watch for new windows opening in --app mode and apply this toggle automatically. You could also probably do it in a hacky way just by launching your app from a bash script which then sleeps for a short time and applies the toggle via IPC. That said, it would be nicest for config readability if this kind of behavior could live within a window rule instead.

[Y-jiji]

I spawned a monitor process on niri startup to listen to window open events.

#!/bin/sh
# Auto windowed-fullscreen daemon for niri.
# Watches the event stream for newly opened windows and toggles
# windowed fullscreen on them, so applications believe they are
# fullscreen and drop their frame buttons.

niri msg --json event-stream | while read -r line; do
  # Collect existing window ids from the initial bulk event.
  case "$line" in
    '{"WindowsChanged":'*)
      known=$(printf '%s' "$line" \
        | sed 's/.*"windows":\[//;s/\].*//' \
        | grep -o '"id":[0-9]*' \
        | grep -o '[0-9]*' \
        | tr '\n' ' ')
      ;;
    '{"WindowOpenedOrChanged":'*)
      id=$(printf '%s' "$line" | grep -o '"id":[0-9]*' | head -1 | grep -o '[0-9]*')
      case " $known " in
        *" $id "*) ;;  # already known, just a property change
        *)
          known="$known $id"
          niri msg action toggle-windowed-fullscreen --id "$id"
          ;;
      esac
      ;;
    '{"WindowClosed":'*)
      id=$(printf '%s' "$line" | grep -o '"id":[0-9]*' | head -1 | grep -o '[0-9]*')
      known=$(printf '%s' "$known" | sed "s/ *$id */ /g")
      ;;
  esac
done