### Godot version

v4.0.beta16.official [518b9e580]

### System information

Windows 10

### Issue description

`RichTextLabel` with `threaded` enabled may crash the game or show the following warning if the node is in another scene:

```
W 0:00:03:0802   test.gd:12 @ load_with_scene(): A Thread object has been re-started without wait_to_finish() having been called on it. Please do so to ensure correct cleanup of the thread.
  <C++ Source>   core/os/thread.cpp:76 @ start()
  <Stack Trace>  test.gd:12 @ load_with_scene()
                 test.gd:6 @ load_items()
                 test.gd:26 @ _on_button_pressed()
```

It may crash the game (without any warning) if it's added directly.

In `v4.0.beta15.official [4fa6edc88]` I was able to reproduce the same warning on my project but I can't reproduce it in the attached MRP. I get a different error and will crash too if the node is added directly:

```
E 0:00:03:0019   remove_from_group: Condition "!E" is true.
  <C++ Source>   scene/main/scene_tree.cpp:157 @ remove_from_group()
```


### Steps to reproduce

Click on the  `Load with scene` or `Load with node` buttons in the attached MRP until it shows a warning/error or crashes. It may take a while.

### Minimal reproduction project

[add_chid_bug_b16.zip](https://github.com/godotengine/godot/files/10521402/add_chid_bug_b16.zip)

if (count != 0) {
				hb_tag_t *script_tags = (hb_tag_t *)memalloc(count * sizeof(hb_tag_t));
				hb_ot_layout_table_get_script_tags(hb_face, HB_OT_TAG_GPOS, 0, &count, script_tags);
				for (unsigned int i = 0; i < count; i++) {
					p_font_data->supported_scripts.insert(script_tags[i]);
				}
				memfree(script_tags);
			}
			
			TT_OS2 *os2 = (TT_OS2 *)FT_Get_Sfnt_Table(fd->face, FT_SFNT_OS2);
			if (os2) {
				if ((os2->ulUnicodeRange1 & 1L << 4) || (os2->ulUnicodeRange1 & 1L << 5) || (os2->ulUnicodeRange1 & 1L << 6) || (os2->ulUnicodeRange1 & 1L << 31) || (os2->ulUnicodeRange2 & 1L << 0) || (os2->ulUnicodeRange2 & 1L << 1) || (os2->ulUnicodeRange2 & 1L << 2) || (os2->ulUnicodeRange2 & 1L << 3) || (os2->ulUnicodeRange2 & 1L << 4) || (os2->ulUnicodeRange2 & 1L << 5) || (os2->ulUnicodeRange2 & 1L << 6) || (os2->ulUnicodeRange2 & 1L << 7) || (os2->ulUnicodeRange2 & 1L << 8) || (os2->ulUnicodeRange2 & 1L << 9) || (os2->ulUnicodeRange2 & 1L << 10) || (os2->ulUnicodeRange2 & 1L << 11) || (os2->ulUnicodeRange2 & 1L << 12) || (os2->ulUnicodeRange2 & 1L << 13) || (os2->ulUnicodeRange2 & 1L << 14) || (os2->ulUnicodeRange2 & 1L << 15) || (os2->ulUnicodeRange2 & 1L << 30) || (os2->ulUnicodeRange3 & 1L << 0) || (os2->ulUnicodeRange3 & 1L << 1) || (os2->ulUnicodeRange3 & 1L << 2) || (os2->ulUnicodeRange3 & 1L << 4) || (os2->ulUnicodeRange3 & 1L << 5) || (os2->ulUnicodeRange3 & 1L << 18) || (os2->ulUnicodeRange3 & 1L << 24) || (os2->ulUnicodeRange3 & 1L << 25) || (os2->ulUnicodeRange3 & 1L << 26) || (os2->ulUnicodeRange3 & 1L << 27) || (os2->ulUnicodeRange3 & 1L << 28) || (os2->ulUnicodeRange4 & 1L << 3) || (os2->ulUnicodeRange4 & 1L << 6) || (os2->ulUnicodeRange4 & 1L << 15) || (os2->ulUnicodeRange4 & 1L << 23) || (os2->ulUnicodeRange4 & 1L << 24) || (os2->ulUnicodeRange4 & 1L << 26)) {
					p_font_data->supported_scripts.insert(HB_SCRIPT_COMMON);
				}
				if ((os2->ulUnicodeRange1 & 1L << 0) || (os2->ulUnicodeRange1 & 1L << 1) || (os2->ulUnicodeRange1 & 1L << 2) || (os2->ulUnicodeRange1 & 1L << 3) || (os2->ulUnicodeRange1 & 1L << 29)) {
					p_font_data->supported_scripts.insert(HB_SCRIPT_LATIN);
				}
				if ((os2->ulUnicodeRange1 & 1L << 7) || (os2->ulUnicodeRange1 & 1L << 30)) {
					p_font_data->supported_scripts.insert(HB_SCRIPT_GREEK);
				}
				if (os2->ulUnicodeRange1 & 1L << 8) {
					p_font_data->supported_scripts.insert(HB_SCRIPT_COPTIC);
				}
				if (os2->ulUnicodeRange1 & 1L << 9) {
					p_font_data->supported_scripts.insert(HB_SCRIPT_CYRILLIC);
				}
				if (os2->ulUnicodeRange1 & 1L << 10) {
					p_font_data->supported_scripts.insert(HB_SCRIPT_ARMENIAN);
				}
				if (os2->ulUnicodeRange1 & 1L << 11) {