kwin-resize-window

Small CLI that resizes and moves application windows by name pattern. Detects the session at runtime: on KDE Plasma + Wayland it talks to KWin via D-Bus scripting; on X11 it falls back to wmctrl or xdotool. Built mostly to force apps to a consistent 1920x1080 for screenshots without dragging window borders around.

Usage

What you'd usually want:

resize-window -w qbz -s 1920x1080

Generic for any app:

resize-window -w firefox -s 1600x900 -c       # -c = center on screen
resize-window -w "com.blitzfc.qbz" -l         # list matching windows
resize-window -w code -s 1280x720 -p 100,50   # size + position
resize-window -h

Auto-detection: KDE + Wayland goes through KWin scripting via qdbus6. On X11 it uses wmctrl or xdotool automatically.

Install

Drop the script anywhere on your PATH:

install -m 0755 resize-window ~/.local/bin/resize-window

Requirements: qdbus6 (or qdbus) and dbus-monitor for the KDE Wayland backend; wmctrl or xdotool for the X11 backend.

Notes

Things the script already handles, worth knowing if you ever modify it:

• KWin 6 doesn't expose Qt.rect() — frameGeometry must be assigned a plain {x, y, width, height} object.
• KWin's print() output isn't captured by journalctl or ~/.xsession-errors, so feedback is reported via an org.freedesktop.Notifications.Notify D-Bus call captured by dbus-monitor.
• Matching is against resourceClass / resourceName only (not the window caption), because titles often contain the cwd or document name and cause false positives.

License

MIT