### Godot version

master ([06ccbfe](https://github.com/godotengine/godot/commit/06ccbfe8eec6e840db3df2360dc2804386f940b8))

### System information

PopOS 22.04

### Issue description

Sometimes the doc page is broken when the engine is closed and then restarted.
Closing the doc and opening it again fixes it.

![2023-05-27_22-15](https://github.com/godotengine/godot/assets/3624853/ed202a55-03e8-420a-bc1c-ccfc7f7cd02a)


### Steps to reproduce

- Open a documentation page for any node
- Restart Godot

### Minimal reproduction project

NA

EDIT : Added the commit hash @Calinou 
if ((p_selection.to_item != nullptr) && (p_selection.to_item->index < l.from->index)) {
			continue;
		}
		if ((p_selection.from_item != nullptr) && (p_selection.from_item->index >= end_idx)) {
			continue;
		}
		if (it->type == ITEM_DROPCAP) {
			const ItemDropcap *dc = static_cast<ItemDropcap *>(it);
			txt += dc->text;
		} else if (it->type == ITEM_TEXT) {
			const ItemText *t = static_cast<ItemText *>(it);
			txt += t->text;
		} else if (it->type == ITEM_NEWLINE) {
			txt += "\n";
		} else if (it->type == ITEM_IMAGE) {
			txt += " ";
		}
	}
	if ((l.from != nullptr) && (p_frame == p_selection.to_frame) && (p_selection.to_item != nullptr) && (p_selection.to_item->index >= l.from->index) && (p_selection.to_item->index < end_idx)) {
		txt = txt.substr(0, p_selection.to_char);
	}
	if ((l.from != nullptr) && (p_frame == p_selection.from_frame) && (p_selection.from_item != nullptr) && (p_selection.from_item->index >= l.from->index) && (p_selection.from_item->index < end_idx)) {
		txt = txt.substr(p_selection.from_char, -1);
	}
	return txt;
}
void RichTextLabel::set_context_menu_enabled(bool p_enabled) {
	context_menu_enabled = p_enabled;
}
bool RichTextLabel::is_context_menu_enabled() const {