### Godot version

v4.1.stable.official [970459615]

### System information

Godot v4.1.stable - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce MX330 (NVIDIA; 30.0.15.1169) - 11th Gen Intel(R) Core(TM) i5-1135G7 @ 2.40GHz (8 Threads)

### Issue description

Calling `RichTextLabel`'s `select_all` method has no visual indicator, but it must have one. 

### Steps to reproduce

- Add `RichTextLabel` node
- Set `selection_enabled` value to be `true`
- Call `$RichTextLabel.select_all() `method in `_ready`

### Minimal reproduction project

[RichTextLabel_bug.zip](https://github.com/godotengine/godot/files/12098913/RichTextLabel_bug.zip)

const_cast<RichTextLabel *>(this)->_validate_line_caches();
	int tg = 0;
	Item *it = main;
	while (it) {
		if (it->type == ITEM_FRAME) {
			ItemFrame *f = static_cast<ItemFrame *>(it);
			for (int i = 0; i < (int)f->lines.size(); i++) {
				MutexLock lock(f->lines[i].text_buf->get_mutex());
				tg += TS->shaped_text_get_glyph_count(f->lines[i].text_buf->get_rid());
			}
		}
		it = _get_next_item(it, true);
	}
	return tg;
}
Size2 RichTextLabel::get_minimum_size() const {
	Size2 sb_min_size = theme_cache.normal_style->get_minimum_size();
	Size2 min_size;
	if (fit_content) {
		min_size.x = get_content_width();
		min_size.y = get_content_height();
	}
	return sb_min_size +
			((autowrap_mode != TextServer::AUTOWRAP_OFF) ? Size2(1, min_size.height) : min_size);
}
void RichTextLabel::_generate_context_menu() {