### 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 Glyph *glyphs = TS->shaped_text_get_glyphs(rid);
		int gl_size = TS->shaped_text_get_glyph_count(rid);
		Vector2 gloff = off;
		
		int processed_glyphs_ol = r_processed_glyphs;
		for (int i = 0; i < gl_size; i++) {
			Item *it = _get_item_at_pos(it_from, it_to, glyphs[i].start);
			int size = _find_outline_size(it, p_outline_size);
			Color font_color = _find_color(it, p_base_color);
			Color font_outline_color = _find_outline_color(it, p_outline_color);
			Color font_shadow_color = p_font_shadow_color;
			if ((size <= 0 || font_outline_color.a == 0) && (font_shadow_color.a == 0)) {
				gloff.x += glyphs[i].advance;
				continue;
			}
			
			ItemFade *fade = nullptr;
			Item *fade_item = it;
			while (fade_item) {
				if (fade_item->type == ITEM_FADE) {
					fade = static_cast<ItemFade *>(fade_item);
					break;
				}
				fade_item = fade_item->parent;
			}
			Vector<ItemFX *> fx_stack;
			_fetch_item_fx_stack(it, fx_stack);
			bool custom_fx_ok = true;
			Point2 fx_offset = Vector2(glyphs[i].x_off, glyphs[i].y_off);
			RID frid = glyphs[i].font_rid;