Previewing single post changes frontend doesn't work on block based themes

[walbo]

The preview functionality on block based themes doesn't work.

Steps to reproduce:

1. Activate a block based theme. Ex twentytwentytwo
2. Make some changes to a post/page (without saving)
3. Click on Preview
4. Click on Preview in new tab
5. Confirm that you changes isn't in the preview.

[adamsilverstein]

Thanks for the bug report @walbo - I was able to reproduce this on trunk. No plugins active, twentytwentytwo theme.

• Publish a post
• make some changes in the editor
• click preview in new tab, changes are not visible

Inspecting on the editor page console, I do see a successful autosave fire right when the new tab opens, but somehow the preview isn't using the autosave data.

We might need to open a ticket on the Gutenberg repository for this, I believe the issue lies there.

[adamsilverstein]

Related: ​https://github.com/WordPress/gutenberg/issues/16006

Am testing this further with non block themes and previous WP versions.

[adamsilverstein]

Confirming:

• Not an issue with 5.8
• Not an issue with non block theme (tested twentytwentyone), previews work fine
• Preview do not work in block theme (tested with twentytwentytwo)

Would be great to fix this!

[hellofromTonya]

Thanks @walbo for reporting and @adamsilverstein for investigating. This needs to be reported upstream in Gutenberg as the fix will happen there and then be backported when fixed via an update.

@walbo or @adamsilverstein can you create an issue for this in Gutenberg please? And then add the issue link to this ticket for tracking. Thank you!

[walbo]

Ticket created in the Gutenberg repo: ​https://github.com/WordPress/gutenberg/issues/37463

[hellofromTonya]

Thank you @walbo! I'll close this ticket as reported upstream. Once fixed in Gutenberg, it'll be backported with other updates.

[adamsilverstein]

Thanks @walbo!