Site Editor: inconsistent undo/redo behavior with navigation block

[annezazu]

Description

This came up as part of the FSE Outreach Program's All Things Media exploration. Of note, there are some similar issues here: #37171 #37170 Across the board, there seems to be some inconsistencies here for folks to dig into but trying to open specific use cases for now. There may need to be a tracking issue depending.

Step-by-step reproduction instructions

1. Open Site Editor
2. Add a navigation block and select a menu.
3. Switching which menu the nav block is using.
4. Try to use undo/redo options. Notice that if you had switched nav menus, it doesn't switch back and there's some visual glitching.

Screenshots, screen recording, code snippet

undo.redo.in.site.editor.mov

Environment info

• WordPress 5.9
• Gutenberg 12.6.0
• TT2
• Chrome
• MacOS

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes

[talldan]

Notice that if you had switched nav menus, it doesn't switch back

Hi @annezazu 👋 I think I could reproduce this. From what I can tell, pressing undo works the first time to change the menu back. But then pressing redo doesn't seem to work. I think that's what happens in the video too.

there's some visual glitching.

Does one of the menus have a Page List inside of it? It's hard to tell but it looks like the Page List loading spinner might be momentarily being shown when clicking undo.

This bit I couldn't reproduce, but there might be something more specific needed. Or it may have been fixed in trunk—I know @getdave and @jasmussen have been doing quite a bit of work on improving parts of the nav block.

[annezazu]

That's correct! It seems to break on undo and the page list block is what was being used in the video.

Does one of the menus have a Page List inside of it? It's hard to tell but it looks like the Page List loading spinner might be momentarily being shown when clicking undo.

Yes, I'm seeing that "flashing" too. Thanks for digging in.

[jasmussen]

@getdave and I just confirmed that the Page List comes with a Placeholder that has its own spinner in it. So that could be related.

But from what I can tell, the visual glitching is the new dashed-line placeholder design that very briefly appears in between loads. That issue should very probably be fixed by #38907. I've on my todo a small followup to avoid layout shifts in that loading state, which should polish up the last part of that.

[mrfoxtalbot]

I can still reproduce this using Version 14.2.0

The undo seems to work just fine, it is the re-do that's getting stuck, and only if you edit a different block in between.

Screen.Capture.on.2022-10-10.at.17-53-17.mp4

[getdave]

it is the re-do that's getting stuck

@mrfoxtalbot Thank you for taking the time to test this.

Would it be possible to expand on the problem a little in written form?

• What exactly is the "getting stuck"
• How does this impact the user and how severe to you think it is?
• What are the production steps?

This will really help when contributors start to look into the problem.

[mrfoxtalbot]

Sure @getdave!

These are the steps:

1. Add a navigation block and make some changes to it.
2. Edit some other block in between editing the navigation menu
3. Undo the changes
4. Try to redo some of the changes to the nav block

I noticed that undoing works fine, but the "redo" option seems to stop working altogether if you mix changes to other blocks.

I do not think this is particularly severe, but something is not working as expected and it could have other ramifications.

Thank you!

[Mamaduka]

I think this was fixed by #50911. I can't reproduce the issue when following the steps from @mrfoxtalbot - #38970 (comment).

[mrfoxtalbot]

Yup! I just tested this with 15.8.1 and undo/redo works fine now. Thank you @Mamaduka!