### 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 
saturation = saturation_option->value.to_float();
			}
			float value = 0.8f;
			OptionMap::Iterator value_option = bbcode_options.find("val");
			if (value_option) {
				value = value_option->value.to_float();
			}
			float frequency = 1.0f;
			OptionMap::Iterator frequency_option = bbcode_options.find("freq");
			if (frequency_option) {
				frequency = frequency_option->value.to_float();
			}
			push_rainbow(saturation, value, frequency);
			pos = brk_end + 1;
			tag_stack.push_front("rainbow");
			set_process_internal(true);
		} else if (tag.begins_with("bgcolor=")) {
			String color_str = tag.substr(8, tag.length()).unquote();
			Color color = Color::from_string(color_str, theme_cache.default_color);
			push_bgcolor(color);
			pos = brk_end + 1;
			tag_stack.push_front("bgcolor");
		} else if (tag.begins_with("fgcolor=")) {
			String color_str = tag.substr(8, tag.length()).unquote();
			Color color = Color::from_string(color_str, theme_cache.default_color);
			push_fgcolor(color);
			pos = brk_end + 1;
			tag_stack.push_front("fgcolor");
		} else {
			Vector<String> &expr = split_tag_block;