### Godot version

v4.2.dev.custom_build [c3b0a92c3]

### System information

Debian Linux X11 Xfce

### Issue description

In the following scene tree it is not possible to write anything in `LineEditB`.
![image](https://github.com/godotengine/godot/assets/6299227/ce5f696a-d86a-402f-98f7-6a762f15543e)

I would expect, that it is possible to focus `LineEditB` with a mouse click and write into it.

Regression from #58334

### Steps to reproduce

1. Load and run MRP
2. Mouse Click into the left LineEditB
3. Type Keyboard => No letters appear in the LineEditB

Variant:

1. Load and run MRP
2. Mouse Click into the right LineEditA
3. Mouse Click into the left LineEditB
4. Type Keyboard => Letters appear in LineEditA instead of LineEditB


### Minimal reproduction project

[BugKeyInputRouting.zip](https://github.com/godotengine/godot/files/11994804/BugKeyInputRouting.zip)

ERR_MAIN_THREAD_GUARD;
	if (p_disable == disable_input) {
		return;
	}
	if (p_disable) {
		_drop_mouse_focus();
		_drop_mouse_over();
		_gui_cancel_tooltip();
	}
	disable_input = p_disable;
}
bool Viewport::is_input_disabled() const {
	ERR_READ_THREAD_GUARD_V(false);
	return disable_input;
}
Variant Viewport::gui_get_drag_data() const {
	ERR_READ_THREAD_GUARD_V(Variant());
	return gui.drag_data;
}
PackedStringArray Viewport::get_configuration_warnings() const {
	ERR_MAIN_THREAD_GUARD_V(PackedStringArray());
	PackedStringArray warnings = Node::get_configuration_warnings();
	if (size.x <= 1 || size.y <= 1) {
		warnings.push_back(RTR("The Viewport size must be greater than or equal to 2 pixels on both dimensions to render anything."));
	}
	return warnings;
}
void Viewport::gui_reset_canvas_sort_index() {