Description

I received a "Your website is having technical difficulties" e-mail (The e-mail is in Norwegian, and am just directly translating to English.)

Web site looked like this (again this is Norwegian):

With the recovery link I was able to login and noticed that the Gutenberg plugin had been deactivated.

Denne utvidelsen kunne ikke lastes riktig og er derfor midlertidig stoppet under gjenopprettingsmodus.

En feil av typen E_ERROR ble forårsaket i linje 59 i filen /home/edwiegjz/religionskritikk.no/wp-content/plugins/gutenberg/lib/block-supports/generated-classname.php. Feilmelding: Uncaught Error: Class 'WP_Block_Supports' not found in /home/edwiegjz/religionskritikk.no/wp-content/plugins/gutenberg/lib/block-supports/generated-classname.php:59 Stack trace: #0 /home/edwiegjz/religionskritikk.no/wp-content/plugins/gutenberg/lib/load.php(117): require() #1 /home/edwiegjz/religionskritikk.no/wp-content/plugins/gutenberg/gutenberg.php(213): require_once('/home/edwiegjz/...') #2 /home/edwiegjz/religionskritikk.no/wp-content/plugins/gutenberg/gutenberg.php(20): gutenberg_pre_init() #3 /home/edwiegjz/religionskritikk.no/wp-settings.php(377): include_once('/home/edwiegjz/...') #4 /home/edwiegjz/religionskritikk.no/wp-config.php(68): require_once('/home/edwiegjz/...') #5 /home/edwiegjz/religionskritikk.no/wp-load.php(37): require_once('/home/edwiegjz/...') #6 /home/edwiegjz/religionskritikk.no/wp-login.php(12): require('/home/edwiegjz/...') #7 {main} thrown

Expected behaviour

No fatal error in the Gutenberg plugin. That the site just works as normal.

Actual behaviour

Fatal error.

WordPress information

• WordPress version: 5.5.3
• Gutenberg version: Versjon 10.2.0
• Are all plugins except Gutenberg deactivated? No
• Are you using a default theme (e.g. Twenty Twenty-One)? No

I assume that the Gutenberg plugin version 10.2.0 will not work in the older WordPress version 5.5.3. Upon perhaps autoupdating that the update caused a fatal error.