Hi David,
The site is up and running again.
Let me know if you have more comments. I appreciate the feedback.

So, having fixed the site after my mishap, I was told by our site manager that no fonts are actually loaded from https://fonts.googleapis.com/css. According to him this link appears in the WP original files but isn't actually used in the site itself.

This is from the error.log:

awwww, how lovely to hear that.
If you have any experience/knowledge of WordPress I could use some help, cause I don't know how to get it up and running again. :(

Hi David,
I didn't realized you have more comments on the site.
Unfortunately I tried to resolve a different issue (https://phabricator.wikimedia.org/T305960#7948089) and crashed the site. :(

@WMDE-leszek @Lucas_Werkmeister_WMDE, not sure who is the owner of wdqs-tutorial.toolforge.org
I can't make any changes, I have no writing permissions. Could someone add me to this project?
EDIT: I forgot I can use sudo with SFTP :)
EDIT(2): Oh crap. I tried to edit where WP loads the fonts from in wp-includes/script-loader.php and now the site has crashed. Uploaded the backup of script-loader.php but that didn't solve the problem. Can anyone help?

@dcaro Thanks David. Didn't notice this duplication. Will fix it in WordPress. Cheers!

@Visx I'm not a tech person myself, so I would need help with this.
the project is a tutorial for the Wikidata Query Service. It's built as a WordPress site. Are the privacy violations related to the WordPress platform itself, or something else?
I need to understand where the problem lies, and whether the guy who originally built the site can solve it, or we need someone else.

Hi Lucas,
I'm the only one from WMIL on Phabricator ¯\_(ツ)_/¯

Created task T258394

Tool recreated at https://wdqs-tutorial.toolforge.org/. Thank you Leszek!
Will open a new ticket for the removal of the old wdqs-wmil-tutorial tool.