Post Preview in Firefox Not Working

[edequalsawesome]

Quick summary

Previewing a post on a Premium site with Firefox isn't working as expected -- I'm seeing a page not found error

Steps to reproduce

1. Create a site with the WordPress.com Premium plan on Firefox with a custom domain
2. Create a new post, save as a draft
3. Attempt to preview the post

What you expected to happen

That I would be able to see the post preview

What actually happened

I was taken to a 404 page

Context

5377841-zen

I was originally able to duplicate this on my test site, but for some reason haven't been able to since my initial test -- I've been able to do this reliably when SSP'd in as the customer in the ticket with a draft post there, though. I must have gotten a cookie somewhere along the line for my test site, but I'm able to duplicate it with a new site:

Platform (Simple, Atomic, or both?)

Simple

Theme-specific issue?

No

Browser, operating system and other notes

macOS Firefox 103.0b9, Firefox 102.0.1

Reproducibility

Intermittent

Severity

Some (< 50%)

Available workarounds?

No but the platform is still usable

Workaround details

No response

[github-actions]

Support References

This comment is automatically generated. Please do not edit it.

• 5377841-zen

[supernovia]

Could this be related? #65716

[Robertght]

Isn't it the same as this: #57812 ?

[JoshuaGoode]

Isn't it the same as this: #57812 ?

Yes, I'd consider this a duplicate. Probably easier to reproduce on Firefox due to default security/cookie settings.

[JoshuaGoode]

Copied notes over and closing in favor of #57812