Recents display page blank in

Nextcloud version :
Operating system and version : Debian (QEMU Virtual CPU version 2.5+ (1 cores))
Apache or nginx version : Yes - it would be really useful if the Settings-System page displayed all this info as I can never remember it all
PHP version : 7.3.9

The issue you are facing:

Since upgrade to 18.0.4 the Recents page is blank

Is this the first time you’ve seen this error? : Y

Steps to replicate it:

  1. take a working system on 18.0.2 and update to 18.0.4

The Recents page is now a blank - and it remains so even after several days use by a few hundred users. The annoying Recommendation section on the All Files page above the files list is working, as are Favourites and Activity.

A staging server with the exact same load of apps and customisations is working ok - but it is still on
(yes, I know, it was silly of us to update the live server before the staging but we didn’t expect a problem going from 18.0.2 to 18.0.4 …)

We are happy to have a look at fixing this, but haven’t a clue where to start. Anyone know what should appear in recent, what code builds the recent list, or anything else about it?