Re: mouse not dragging a float window.

with a minor refactoring of the actual resize function:

--8<---------------cut here---------------start------------->8---
(defcommand (esf-resize-window float-group) (dw dh)
  ((:number "dW = ") (:number "dH = "))
  (let* ((window (current-window))
         (parent (window-parent window))
         (w (xlib:drawable-width parent))
         ;; get actual height: ignore title bar
         (h (- (xlib:drawable-height parent) *float-window-title-height*)))
    (float-window-move-resize window
                              :width (+ w dw)
                              :height (+ h dh))))
--8<---------------cut here---------------end--------------->8---

-- 
Eric S Fraga via gnus (Emacs 29.0.50 2022-08-16) on Debian 11.4