Uncaught DOMException: Failed to execute 'remove' on 'DOMTokenList' after upgrade

[hirbod]

• Swiper Version: 6.4.14
• Platform/Target and Browser Versions macOS, every browser

What You Did

EXPLAIN WHAT YOU DID, PREFERABLY WITH CODE EXAMPLES, HERE.

Upgraded from 6.4.5 to 6.4.14

Expected Behavior

EXPLAIN WHAT IS TO BE EXPECTED, HERE.

Since the update, I get a
Uncaught DOMException: Failed to execute 'remove' on 'DOMTokenList': The token provided must not be empty.

Actual Behavior

Should not throw error

[nolimits4web]

Would be great to see minimal live demo with the issue

[hirbod]

My application is HUGE. I just updated from 6.4.5 to 6.4.15 and this issue did appear. I have multiple sliders on my page, I will try to isolate the issue.

[hirbod]

@nolimits4web I did a downgrade from 6.4.14 back to 6.4.5 and the issue is gone. Since the error is happening in DOM7, I guess some changes there introduced the regression

[nolimits4web]

There were no any changes to Dom7 since then. Still need to see live example (Fiddle/CodeSandbox/...) to see know where it comes from

[hirbod]

@nolimits4web the issue is not traceable locally on my development setup but once I deploy in production, it happens. I did few more tests, and even 6.4.12 is working perfectly. The error appears as soon as I upgrade to 6.4.14. It should be easy to trace the differences between the releases to get a clue what has been changed

[hirbod]

@nolimits4web I got the reason now:

I have a ResizeObserver which destroys the swiper if a resize on the container is detected and reinitialize it. And this is breaking since 6.4.14.

  _registerObserver() {
    const ro = new ResizeObserver(() => {
      // this operation is pretty heavy but
      // the recalculation is heavy so we need to reinit
      this.swiper.destroy()
      this._initCarousel()
    })
    ro.observe(this._element.querySelector('.swiper-container'))
  }

[hirbod]

Looks like you were faster than me :D

[chabb]

Thanks, just got the same issue.