Hi Marius,
“Would you mind sharing what you mean by broke”
404 on every page except home.
“what happened”
I was trying to get a new contact form to work, thought it might be a plugin or theme conflict. I used trouble-shooting mode to disable all other plugins and switch to 2017 theme. Boom. Site broke. At least that’s how I remember it. To be honest I was not being too careful and it is entirely possible that I did something completely dunderheaded that had nothing to do with your plugin.
“what was the expected result”
I kinda hoped to get my new contact form working
“and perhaps provide us with some information about what plugins and themes you’ve got?”
Responsive Mobile child theme (very minor tweaks)
Lotsa plugins: Akismet; Classic Editor; Contact Form 7 (this was the new one); Custom Functions by Kenny (I wrote it myself!); Disable WP Rest API; Duplicate Post; Duplicator; Edit Author Slug; Enable Media Replace; Favicon by RealFaviconGenerator; Health Check; Limit Login Attempts Reloaded; LiteSpeed Cache; Menu Icons; Meta Slider; PirateForms Contact Form; Salt Shaker; Sticky Menu (or Anything!) on Scroll; Tiny MCE Advanced; UpdraftPlus; WPS Hide Login; Yoast SEO
To be clear, I have no complaints regarding the plugin, which I love. Just wanted to second your excellent advice to be sure to have a fresh backup.