Description

The undo and redo functionality in the stand-alone widgets editor will break saving with enough persistence. I did not manage to consistently repeat a set of steps but as it can be seen in the screen recording, eventually it breaks.

The customizer instance of the Widgets editor does not have these problems.

Expected behaviour

No matter how many times I undo or redo saving always saves what is visible on the screen.

Actual behaviour

With enough fiddling with the undo/redo functionality the saving will error out.

Screenshots or screen recording (optional)

WordPress information

• WordPress version: Version 5.7.2
• Gutenberg version: Trunk
• Are all plugins except Gutenberg deactivated? Yes
• Are you using a default theme (e.g. Twenty Twenty-One)? Yes

Device information

• Device: Desktop
• Operating system: OSX
• Browser: Safari