### 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)

return line.get_height(theme_cache.line_separation);
}
void RichTextLabel::_update_theme_item_cache() {
	Control::_update_theme_item_cache();
	theme_cache.normal_style = get_theme_stylebox(SNAME("normal"));
	theme_cache.focus_style = get_theme_stylebox(SNAME("focus"));
	theme_cache.progress_bg_style = get_theme_stylebox(SNAME("background"), SNAME("ProgressBar"));
	theme_cache.progress_fg_style = get_theme_stylebox(SNAME("fill"), SNAME("ProgressBar"));
	theme_cache.line_separation = get_theme_constant(SNAME("line_separation"));
	theme_cache.normal_font = get_theme_font(SNAME("normal_font"));
	theme_cache.normal_font_size = get_theme_font_size(SNAME("normal_font_size"));
	theme_cache.default_color = get_theme_color(SNAME("default_color"));
	theme_cache.font_selected_color = get_theme_color(SNAME("font_selected_color"));
	use_selected_font_color = theme_cache.font_selected_color != Color(0, 0, 0, 0);
	theme_cache.selection_color = get_theme_color(SNAME("selection_color"));
	theme_cache.font_outline_color = get_theme_color(SNAME("font_outline_color"));
	theme_cache.font_shadow_color = get_theme_color(SNAME("font_shadow_color"));
	theme_cache.shadow_outline_size = get_theme_constant(SNAME("shadow_outline_size"));
	theme_cache.shadow_offset_x = get_theme_constant(SNAME("shadow_offset_x"));
	theme_cache.shadow_offset_y = get_theme_constant(SNAME("shadow_offset_y"));
	theme_cache.outline_size = get_theme_constant(SNAME("outline_size"));
	theme_cache.bold_font = get_theme_font(SNAME("bold_font"));
	theme_cache.bold_font_size = get_theme_font_size(SNAME("bold_font_size"));
	theme_cache.bold_italics_font = get_theme_font(SNAME("bold_italics_font"));
	theme_cache.bold_italics_font_size = get_theme_font_size(SNAME("bold_italics_font_size"));
	theme_cache.italics_font = get_theme_font(SNAME("italics_font"));
	theme_cache.italics_font_size = get_theme_font_size(SNAME("italics_font_size"));
	theme_cache.mono_font = get_theme_font(SNAME("mono_font"));
	theme_cache.mono_font_size = get_theme_font_size(SNAME("mono_font_size"));