Modal dialog is display outside of the screen (window)

Problem/Motivation

the modal (dialog) isn't displayed in the centre of the browser window on long pages, so you can't do anything because the dialog buttons aren't accessible.

if the window is resized or the screen flipped (on mobile), the modal is repositioned normally.

this may be a core issue.

Steps to reproduce

This happens on long product list pages where you've already scrolled down (for example over 1000px), sometimes it doesn't happen either...

even when the modal (dialog) isn't centred in the screen, I get the following error in the console:

Uncaught TypeError: event.data is null
    resetSize https://www.loka-vaisselle.com/core/misc/dialog/dialog.position.js?v=10.4.6:82
    later https://www.loka-vaisselle.com/core/misc/debounce.js?v=10.4.6:37
    [...]

==>

[...] for (let n = 0; n < positionOptions.length; n++) {
option = positionOptions[n];
optionValue = event.data.settings[option];
if (optionValue) {
// jQuery UI does not support percentages on heights, convert to pixels.
if [...] (

Proposed resolution

As a work around I use this CSS :

div.ui-dialog {
  top: 50% !important;
  left: 50% !important;
  transform: translate(-50%, -50%);
}