Replace ResizeObserver by Resize event

[ludoboludo]

Why are these changes introduced?

Fixes #510

What approach did you take?

Replaced the ResizeObserver by a Resize event which applies to the window instead of just the slider element.

Other considerations

I still need to look into the IntersectionObserver but when I tested on a laptop that has Safari 12.1.2 and browserstack iOS 12, I didn't get errors like I did before and language selector, cart notification, slider and product modal do work.

From what I'm seeing it's just the sticky header and product recos that do not work. So product recos never show up and the header behave like a non sticky one, stays at the top of the page at all time, so you have to scroll back up to get to it.

Would this be acceptable enough ? I think it prevents us from having too many work arounds/extra code and offer a decent experience on those older browser versions.

Demo links

• Store
• Editor

Checklist

• Followed theme code principles
• Linted with Theme Check
• Tested on mobile
• Tested on multiple browsers
• Tested for accessibility

Things to test
Use browserstack to test iOS 12 and the Mojave OS with version 12 for Safari.

• local selector in the footer,
• product modal,
• cart notification,
• and general functionality of the theme

[michaelburtonray]

Is Safari 12 being supported? According to Theme requirements Only the latest two major releases of a browser need support (Safari 14 and Safari 13)

I thought the Dawn theme was supposed to be focusing on the latest browser APIs supported by evergreen browsers as opposed to bloating the codebase with fallbacks and polyfills.

[ludoboludo]

You're right @michaelburtonray 👌 thanks for bringing it up. I will close the PR along with the issue.