Toggled menu closes on screen size change

[dgobnto]

What should happen?

A toggled menu should stay open after a screen size change.

What happens instead?

Menu closes.

Possible Solution

...

Test Case and/or Steps to Reproduce (for bugs)

Test Case: https://codepen.io/koiastudio/pen/QWjZQBW

How to reproduce:

1. Resize screen to 'small' screen size;
2. Toggle the menu;
3. Change screen size to 'medium'.

Context

One consequence is that the aria-expanded value on the element that triggers the toggle remains true, although the menu is now closed.

Your Environment

• Foundation version(s) used: 6.6.3
• Browser(s) name and version(s): All modern browsers
• Device, Operating System and version: macOS 10.13
• Link to your project:

Checklist

• I have read and follow the CONTRIBUTING.md document.
• There are no other issues similar to this one.
• The issue title and template are correctly filled.

[DanielRuf]

It seems we always reset it there:

https://github.com/foundation/foundation-sites/blob/develop/js/foundation.responsiveToggle.js#L88

[DanielRuf]

So far it makes sense to me.

[dgobnto]

I understand that the operation is in accordance with the code instructions (it always is, right?!), but I just don't think that this is the desired behavior. Why should the menu close on screen size change?
On a second note, as mentioned already, at the moment the values of 'aria-expanded' or the toggled class are not updated. This causes a number of issues, namely it becomes impossible to animate the button based on those attributes.

[DanielRuf]

PRs which fix this are very welcome.
We have to check in detail what has to be changed to get a good working solution.