would you mind sharing both segment definitions?

Checkout Success
Visitors who reached a goal id --> matches --> 1

Checkout Success Search intern
Visitors who reached a goal id --> matches --> 1
AND
Search term (internal search) --> does not contain --> testomat

With "Checkout Success Search intern" I get all visitors who bought something and did an internal search, because no one searches for testomat and all other search terms are counted. That worked since 2016.

I guess an empty search term might meanwhile match the does not contain testomat. Did you try it with a segment like searches>0 ?

How do I define this?

Should be something like Number of searches in the UI

Thanks, found it. Test button works. I'll give you feedback if it works after archiving.

I'll get the following error in the UI admin panel when I want to reset historical reports: The segment condition 'searches&gt' is not valid.

Are you using the Invalidate Reports plugin?

Yes

Thanks for your patience with this issue. We believe this has been resolved in the recent updates of Matomo. To ensure you have the fix, please update to the latest version of Matomo. If the issue persists after the update, don't hesitate to reopen this issue and let us know. Cheers!