GNU bug report logs - #75053
Xwidget widgets shorter than the window height do not scroll correctly

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Subject: Xwidget widgets shorter than the window height do not scroll correctly
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Xwidget widgets do not stay "in place" as the text they are placed in is =
scrolled, unlike images and other non-character-sized content.

To reproduced, create a new xwidget of a fixed pixel size that does not =
occupy the full window height:

(require 'xwidget)
(let ((xw (make-xwidget 'webkit "Test" (- (window-pixel-width) 20) =
400)))
  (xwidget-webkit-goto-uri xw "https://www.gnu.org")
  (goto-char (point-max))
  (insert "\n\n\n" (propertize "     " 'display `(xwidget :xwidget ,xw)) =
"\n\nMORE STUFF BELOW\n"))

Scrolling in the buffer (even via simple (scroll-up/down N) calls), =
leads to displacement between the text and the widget itself, resulting =
in overlap.  I.e. the text scrolls, the widget does not.

This tends to resolve with more movement, but in a "jumping" fashion.

Tested on Emacs 29.4 NS and emacs-mac; similar behavior (though =
emacs-mac can partially scroll the image off-screen, unlike NS).