Gutenberg error writing post - The editor has encountered an unexpected error. Attempt Recovery Copy Post Text Copy Error

[KaylaACM]

Trying to write posts on WordPress with Gutenberg. It stops suddenly and this error comes up. Clicking attempt recovery does nothing.

[talldan]

@KaylaACM Could you click Copy Error and paste the output in a comment here. Thanks.

[mprior92]

I'm constantly getting the same error.

TypeError: Cannot read property 'attributes' of null

[talldan]

Thanks for sharing the error. Unfortunately that's quite difficult to track down as attributes is used in a lot of place. I hoped the error would have a stack trace with it.

@mprior92 if you open the browser dev tools when the error comes up (right click somewhere on the page and select 'Inspect Element') and then switch to the console tab. If there's red text there it'd be great if you could screenshot it and post it here.

[KaylaACM]

Error: An error occurred while running 'mapSelect': u.substr is not a function
The error may be correlated with this previous error:
TypeError: u.substr is not a function
at v (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/build/block-serialization-default-parser/index.js?ver=7110f347451a9a2bcae6223b180b96dd:1:3536)
at b (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/build/block-serialization-default-parser/index.js?ver=7110f347451a9a2bcae6223b180b96dd:1:2843)
at p (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/build/block-serialization-default-parser/index.js?ver=7110f347451a9a2bcae6223b180b96dd:1:2342)
at Gr (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/build/blocks/index.js?ver=c8e8f699f604ff1628eaf1863098f07a:13:36982)
at https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/build/block-editor/index.js?ver=111d02e55937608149e0d53ccb3d5ab2:25:51819
at u (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/build/block-editor/index.js?ver=111d02e55937608149e0d53ccb3d5ab2:1:10419)
at i (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/build/block-editor/index.js?ver=111d02e55937608149e0d53ccb3d5ab2:25:49769)
at Array.map ()
at https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/build/block-editor/index.js?ver=111d02e55937608149e0d53ccb3d5ab2:25:50158
at u (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/build/block-editor/index.js?ver=111d02e55937608149e0d53ccb3d5ab2:1:10419)

Original stack trace:
at Xe (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/build/data/index.js?ver=a0effe22ca5a445ba9c4ee384cdf7853:1:28482)
at https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/build/data/index.js?ver=a0effe22ca5a445ba9c4ee384cdf7853:1:29038
at we (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/vendor/react-dom.min.de439aae.js:84:293)
at He (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/vendor/react-dom.min.de439aae.js:97:464)
at zj (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/vendor/react-dom.min.de439aae.js:228:406)
at Th (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/vendor/react-dom.min.de439aae.js:152:223)
at tj (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/vendor/react-dom.min.de439aae.js:152:152)
at Te (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/vendor/react-dom.min.de439aae.js:146:151)
at https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/vendor/react-dom.min.de439aae.js:61:68
at unstable_runWithPriority (https://adrianchambersmotorsports.com.au/wp-content/plugins/gutenberg/vendor/react.min.e713ea3b.js:25:260)

[KaylaACM]

[talldan]

Thanks @KaylaACM. This is something that will be fixed in an upcoming version of the Gutenberg plugin.

It's a bad bug that's triggered by having an empty reusable block on your site. As a temporary workaround you can remove the empty reusable block from your site, or add something to it. Some instructions here - #26381 (comment)

Sorry that you've been affected by this one!

[talldan]

Closing as this has since been fixed (and I know the website in question was able to resolve the issue).