Drag and drop of a Heading text box does not work on Firefox 96

[AndreeaChi]

Steps to reproduce on Firefox 96:

1. Edit a diagram page
2. From General shapes try to drag and drop a Heading text box.

Expected result: the drag and drop is possible, the box is displayed where it was dropped.

Actual result: when trying to drag the Heading text box it selects a number of texts from the entire screen. When reaching with the drag the diagram edit section and trying to drop it, it does not remain where it is dropped.

If clicked on the Heading Text box it is added in the diagram edit section along with other shapes.
The issue does not happen on Chrome 97.

[snazare]

reproducing on ff 120.0.1 XWiki 15.10.10

[snazare]

to check if it reproduces on drawio

[lamblinc]

Can reproduce partially on Chromium 128 / XWiki 15.10 / Diagram 1.20.5 : some texts in the page are highlighted, but the drop occurs where it should. This happens with all kind of shapes, not only Headings.

In FF 129 and same configuration, bug still there (drop problem + highlights) and only occurs with Headings.

In native draw.io (online, 24.7.7) : no bugs under Firefox or Chromium.