Gutenberg: Immediate crash of editor upon opening new post page (solved by updating nginx config)

Created on 6 Dec 2018 · 20Comments · Source: WordPress/gutenberg

Describe the bug
Upon opening the "new post" page, the editor is briefly visible before being replaced by a "The editor has encountered an unexpected error." popup. There is a button "attempt recovery", which does not work.

To Reproduce
Steps to reproduce the behavior:

Go to the "new post" page
See error

Expected behavior
not see error.

Screenshots
selection_002

Desktop (please complete the following information):

OS: Ubuntu 16.04
Browser Firefox
Version 63

Additional context
The Gutenberg editor in wordpress 5.0. I cleared my localStorage settings but the error remains.

* Copies error *

this.wp.editor</Hs</<@https://kilianvalkhof.com/wp-includes/js/dist/editor.min.js?ver=9.0.4:55:239952
i@https://kilianvalkhof.com/wp-includes/js/dist/vendor/lodash.min.js?ver=4.17.11:6:91
x/An.filter@https://kilianvalkhof.com/wp-includes/js/dist/vendor/lodash.min.js?ver=4.17.11:99:327
this.wp.editor</Hs<@https://kilianvalkhof.com/wp-includes/js/dist/editor.min.js?ver=9.0.4:55:239921
ph@https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:97:88
eg@https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:125:307
fg@https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:126:168
wc@https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:138:237
fa@https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:137:115
gg@https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:135:196
Ca@https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:133:365
enqueueSetState@https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:191:324
q.prototype.setState@https://kilianvalkhof.com/wp-includes/js/dist/vendor/react.min.js?ver=16.6.3:20:291
value@https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:13979
n/<@https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:10354
n@https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:10325
g/<.subscribe</<@https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:8324
b@https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:19536
y/</<@https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:5320
v/</</<@https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:5748
l/</</<@https://kilianvalkhof.com/wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:9095
dispatch@https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:22001
a/<@https://kilianvalkhof.com/wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:8676
r/<@https://kilianvalkhof.com/wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:4477
r@https://kilianvalkhof.com/wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:4451
u/<@https://kilianvalkhof.com/wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:4406
j/</<@https://kilianvalkhof.com/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:2:29352
j/<@https://kilianvalkhof.com/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:2:29220
f@https://kilianvalkhof.com/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:1:20743

[Status] Needs More Info [Type] Help Request

Source

Kilian

😕3

Most helpful comment

Fixed

tldr: if you run Nginx, you might need to update your nginx config.

I have the same problem. With posts only. Pages work fine.

This made me check. The editor works fine for pages, it's just the posts that crash.

[...] error was solved by changing the permalink structure (and eventually the rewrite rules on the server)

I indeed have a custom permalink structure: /%year%/%category%/%postname%/, with what was then the default digitalocean configuration/tutorial for wordpress with permalinks on Nginx. I checked a current tutorial and I noticed that I had $is_args$args missing from the main location block:

    location / {
        try_files $uri $uri/ /index.php$is_args$args;
    }

After adding this to the end of /index.php, the editor now works for posts too!

Kilian on 10 Dec 2018

👍18 🎉7 🚀5

All 20 comments

Hi @Kilian,

Thanks for the report! I'm unable to reproduce this in WordPress 5.0.

A couple follow-up questions:

Are you running any other plugins? Can you try deactivating them to see if one might be the cause?
Can you open Developer Tools in your browser to see if any script requests (or other HTTP requests) may have failed?

danielbachhuber on 6 Dec 2018

Got 2 reports from our customers on that as well, unfortunately :( Trying to debug remotely but it's individual customer's computers. Mostly Chrome. Will try to provide more details soon

At this moment clearing the cache and cookies helps temporarily.

pojke on 6 Dec 2018

Hi, I also have this problem.
Firefox Developer Console display this:

Unhandled promise rejection Error: "[object Object]"          wp-polyfill.min.js:2:29718
    r wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:8606
    r wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:8564
    j wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:2:29352
    j wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:2:29220
    f wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:1:20743

T/</n<           wp-includes/js/dist/vendor/wp-polyfill.min.js:2:29718
[89]</n.exports  wp-includes/js/dist/vendor/wp-polyfill.min.js:1:25719
T/<              wp-includes/js/dist/vendor/wp-polyfill.min.js:2:29595
[51]</n.exports  wp-includes/js/dist/vendor/wp-polyfill.min.js:1:16271
<anonymous>      wp-includes/js/dist/vendor/wp-polyfill.min.js:1:30590
m                wp-includes/js/dist/vendor/wp-polyfill.min.js:1:30435
x                wp-includes/js/dist/vendor/wp-polyfill.min.js:1:30455

AlirezaSedghi on 7 Dec 2018

@danielbachhuber I run many plugins, but none that should change the edit view too much. I'll try regardless. In the mean time. Worthy of note is that my Wordpress database has been with me since 2006, so it has had a fair number of migrations.

Additionally, the error in devtools provides slightly more context compared to the 'copy error' text:

TypeError: "e.visibility is undefined"
    Hs https://kilianvalkhof.com/wp-includes/js/dist/editor.min.js?ver=9.0.4:55:239952
    i https://kilianvalkhof.com/wp-includes/js/dist/vendor/lodash.min.js?ver=4.17.11:6:91
    filter https://kilianvalkhof.com/wp-includes/js/dist/vendor/lodash.min.js?ver=4.17.11:99:327
    Hs https://kilianvalkhof.com/wp-includes/js/dist/editor.min.js?ver=9.0.4:55:239921
    ph https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:97:88
    eg https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:125:307
    fg https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:126:168
    wc https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:138:237
    fa https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:137:115
    gg https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:135:196
    Ca https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:133:365
    enqueueSetState https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:191:324
    setState https://kilianvalkhof.com/wp-includes/js/dist/vendor/react.min.js?ver=16.6.3:20:291
    value https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:13979
    n https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:10354
    n https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:10325
    subscribe https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:8324
    b https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:19536
    y https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:5320
    v https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:5748
    l https://kilianvalkhof.com/wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:9095
    dispatch https://kilianvalkhof.com/wp-includes/js/dist/data.min.js?ver=4.0.1:1:22001
    a https://kilianvalkhof.com/wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:8676
    r https://kilianvalkhof.com/wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:4477
    r https://kilianvalkhof.com/wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:4451
    u https://kilianvalkhof.com/wp-includes/js/dist/redux-routine.min.js?ver=3.0.3:1:4406
    j https://kilianvalkhof.com/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:2:29352
    j https://kilianvalkhof.com/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:2:29220
    f https://kilianvalkhof.com/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:1:20743
 react-dom.min.js:104:245

Furthermore i get a 403 on https://public-api.wordpress.com/pinghub/wpcom/me/newest-note-data

Edit: On chrome 71, the editor crashes still but the actual error is different:

TypeError: Cannot read property 'show_ui' of undefined
    at https://kilianvalkhof.com/wp-includes/js/dist/editor.min.js?ver=9.0.4:55:239972
    at i (https://kilianvalkhof.com/wp-includes/js/dist/vendor/lodash.min.js?ver=4.17.11:6:91)
    at An.filter (https://kilianvalkhof.com/wp-includes/js/dist/vendor/lodash.min.js?ver=4.17.11:99:338)
    at https://kilianvalkhof.com/wp-includes/js/dist/editor.min.js?ver=9.0.4:55:239937
    at ph (https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:97:88)
    at eg (https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:125:307)
    at fg (https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:126:168)
    at wc (https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:138:237)
    at fa (https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:137:115)
    at gg (https://kilianvalkhof.com/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:135:196)

Kilian on 7 Dec 2018

❤2

Thanks for the additional data, @Kilian.

Edit: On chrome 71, the editor crashes still but the actual error is different:
 TypeError: Cannot read property 'show_ui' of undefined

This is helpful. It seems like there are some additional recent reports in https://github.com/WordPress/gutenberg/issues/9556#issuecomment-443546483

Also, #8802 is an earlier report.

The immediate problem is that Gutenberg is trying to access data about taxonomies, but the show_ui field isn't available. There's likely some deeper root cause though.

Can you take a look at your "Network" tab in your browser's Developer Tools to see if any API requests are failed? And, if so, share screenshots of those?

Furthermore i get a 403 on https://public-api.wordpress.com/pinghub/wpcom/me/newest-note-data

This is a Jetpack issue and likely unrelated (but you never know).

danielbachhuber on 7 Dec 2018

Other than the 403 mentioned there are no other failed requests.

Kilian on 7 Dec 2018

I noticed that https://github.com/WordPress/gutenberg/issues/8899#issuecomment-413318042 mentions the Cannot read property 'show_ui' of undefined error was solved by changing the permalink structure (and eventually the rewrite rules on the server). @Kilian can you note whether you're using a custom permalink and what that is? If you update the permalink settings, does it make the problem go away? See https://github.com/WordPress/gutenberg/issues/8899#issuecomment-413318042

designsimply on 8 Dec 2018

👍1

I'm seeing the same errors as @Kilian in Chrome. Disabling my plugins did not solve the problem for me.

mdparker on 8 Dec 2018

I have the same problem. With posts only. Pages work fine.

I run Nginx v1.14.0 with PHP-FPM v7.2.11
My website is set as example.com/subdir/

All plugins are disabled, permalinks re-saved.

Update: The problem is gone when permalinks are set to "Plain", but persists when permalinks are set to "Post name".

No relevant message in Nginx error log (debug level).

Here is something from access log:

IP - User [08/Dec/2018:19:19:06 +0000] "POST /subdir/wp-json/wp/v2/pages/703/autosaves?_locale=user HTTP/2.0" 404 169 "https://example.com/subdir/wp-admin/post.php?post=703&action=edit" "Mozilla/5.0 (X11; Linux x86_64; rv:65.0) Gecko/20100101 Firefox/65.0"
IP - User [08/Dec/2018:19:19:07 +0000] "GET /subdir/wp-json/wp/v2/users/?who=authors&per_page=100&_locale=user HTTP/2.0" 404 169 "https://example.com/subdir/wp-admin/post-new.php?post_type=page" "Mozilla/5.0 (X11; Linux x86_64; rv:65.0) Gecko/20100101 Firefox/65.0"
IP - User [08/Dec/2018:19:19:07 +0000] "GET /subdir/wp-json/wp/v2/taxonomies?context=edit&_locale=user HTTP/2.0" 404 169 "https://example.com/subdir/wp-admin/post-new.php?post_type=page" "Mozilla/5.0 (X11; Linux x86_64; rv:65.0) Gecko/20100101 Firefox/65.0"
IP - User [08/Dec/2018:19:19:16 +0000] "POST /subdir/wp-json/wp/v2/pages/703/autosaves?_locale=user HTTP/2.0" 404 169 "https://example.com/subdir/wp-admin/post.php?post=703&action=edit" "Mozilla/5.0 (X11; Linux x86_64; rv:65.0) Gecko/20100101 Firefox/65.0"
IP - User [08/Dec/2018:19:19:27 +0000] "POST /subdir/wp-json/wp/v2/pages/703/autosaves?_locale=user HTTP/2.0" 404 169 "https://example.com/subdir/wp-admin/post.php?post=703&action=edit" "Mozilla/5.0 (X11; Linux x86_64; rv:65.0) Gecko/20100101 Firefox/65.0"

Firefox Developer Edition Console:

TypeError: "e.visibility is undefined; can't access its "show_ui" property"

        Hs https://example.com/subdir/wp-includes/js/dist/editor.min.js?ver=9.0.4:55
    i2Lodash

    Hs https://example.com/subdir/wp-includes/js/dist/editor.min.js?ver=9.0.4:55
    ph https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:97
    eg https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:125
    fg https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:126
    wc https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:138
    fa https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:137
    gg https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:135
    Ca https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:133
    enqueueSetState https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:191
    setState https://example.com/subdir/wp-includes/js/dist/vendor/react.min.js?ver=16.6.3:20
    value https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1
    n https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1
    n https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1
    subscribe https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1
    b https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1
    y https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1
    v https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1
    l Redux dispatch https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1
a4Redux

        j https://example.com/subdir/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:2
        j https://example.com/subdir/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:2
        f https://example.com/subdir/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:1

react-dom.min.js:104:245

    Pf https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:104 callback https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:113 uf https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:65 tf https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:65 zc https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:146 wc https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:138 fa https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:137 gg https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:135 Ca https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:133 enqueueSetState https://example.com/subdir/wp-includes/js/dist/vendor/react-dom.min.js?ver=16.6.3:191 setState https://example.com/subdir/wp-includes/js/dist/vendor/react.min.js?ver=16.6.3:20 value https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1 n https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1 n https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1 subscribe https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1 b https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1 y https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1 v https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1 l Redux

dispatch https://example.com/subdir/wp-includes/js/dist/data.min.js?ver=4.0.1:1 a4Redux

    j https://example.com/subdir/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:2 j https://example.com/subdir/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:2 f https://example.com/subdir/wp-includes/js/dist/vendor/wp-polyfill.min.js?ver=7.0.0:1

ghost on 8 Dec 2018

Same error here, too. Wordpress 5.0 upgrade completed a day or two ago (I came here from another issue referencing this one).

Plugins all disabled but exact same error i.e. momentary display of the editor that's then replaced by the error reported here. Disabling Gutenberg removes the problem.

digitalformula on 9 Dec 2018

same error, if you are trying to create a new block from manage all reusable blocks

wp-admin/post-new.php?post_type=wp_block

umakantsharmacedcoss on 10 Dec 2018

Fixed

tldr: if you run Nginx, you might need to update your nginx config.

I have the same problem. With posts only. Pages work fine.

This made me check. The editor works fine for pages, it's just the posts that crash.

[...] error was solved by changing the permalink structure (and eventually the rewrite rules on the server)

    location / {
        try_files $uri $uri/ /index.php$is_args$args;
    }

After adding this to the end of /index.php, the editor now works for posts too!

Kilian on 10 Dec 2018

👍18 🎉7 🚀5

Thanks for the update, @Kilian.

The specific issue you found make sense to me. If your Nginx configuration was incorrect, then ?context=edit wasn't passing through to WordPress which meant you'd get a Taxonomy object with ?context=view (and, thus, missing its visibility attribute).

It was only a problem with Posts for you because you don't have any taxonomies assigned to Pages.

danielbachhuber on 10 Dec 2018

Unfortunately, my issue is different so I'll log a new bug

pojke on 12 Dec 2018

👍1

I can confirm the issue, same browser version and OS.
The nginx configuration is OK, already checked this.

stz184 on 13 Dec 2018

Exact same issue here. Still remains with WP 5.0.2.

FreeBSD 11.1
Apache 2.4.37
Chrome and FF

micele on 20 Dec 2018

👍1

@AlirezaSedghi the error in your case is a little different. Can you please report your case at https://github.com/WordPress/gutenberg/issues/12982 and include your WordPress, OS, and browser versions?

@mdparker @igortitarenko @digitalformula if you haven't already, please try the solution posted at https://github.com/WordPress/gutenberg/issues/12655#issuecomment-445816958 if you are using nginx.

@umakantsharmacedcoss issues with wp-admin/post-new.php?post_type=wp_block may be different. Could you please post the details of your case at https://github.com/WordPress/gutenberg/issues/12324 ?

@stz184 @micele I would like to close this issue since it's getting very long and because one solution that is working for some was posted so it's possible your issue may be different. Would you mind please opening a new issue with the details of your case including: the error you see on screen, the error you see in your browser console, WordPress version, OS & browser version, note whether you've tested with all plugins deactivated, and your the location rule from your nginx config (or the corresponding rule in Apache if you are using Apache)?

designsimply on 21 Dec 2018

@designsimply No nginx here. It's Apache 2.4.17 on FreeBSD.

mdparker on 22 Dec 2018

@designsimply ~~Apologies for the delayed response - I missed the notification that you tagged people.~~

~~Yes, I'm running Nginx. I've added $is_args$args in the relevant place, as outlined by the linked comment and restarted Nginx. Issue is still there.~~

~~My permalink structure is the same as the one in the linked comment i.e. /%year%/%category%/%postname%/ (it was /%postname%/ but I changed it for testing).~~

No difference for me, unfortunately. Exact same error manifested in the exact same way. The message saying welcome to the world of blocks appears momentarily, then is replaced by The editor has encountered an unexpected error.

Ignore the above, sorry. I found my server was configured in a way that pointed me to the wrong site conf file. After finding I was editing the wrong conf file and then making the changes in the correct one, everything seems to working.

Thanks for following up on this!

digitalformula on 15 Jan 2019

🎉1

Fixed

tldr: if you run Nginx, you might need to update your nginx config.

I have the same problem. With posts only. Pages work fine.

This made me check. The editor works fine for pages, it's just the posts that crash.

[...] error was solved by changing the permalink structure (and eventually the rewrite rules on the server)

I indeed have a custom permalink structure: /%year%/%category%/%postname%/, with what was then the default digitalocean configuration/tutorial for wordpress with permalinks on Nginx. I checked a current tutorial and I noticed that I had $is_args$args missing from the main location block:
    location / {
        try_files $uri $uri/ /index.php$is_args$args;
    }
After adding this to the end of /index.php, the editor now works for posts too!

Thanks!

It's fairly simple to assume its a URL re-write issue when changing the default behavior in WordPress can resolve this issue. For those on Apache, you will need a similar mod.

Perhaps the codex needs updating to include this? Link