Illegal mix of collations OJS 3.2.1

After upgrading from OJS 2.4.8 to 3.2.1-1 searches simply return a blank page.
The error log shows entries like this:

PHP Fatal error: Uncaught Exception: DB Error: Illegal mix of collations (utf8_general_ci,IMPLICIT) and (utf8_unicode_ci,IMPLICIT) for operation ‘=’ Query:

Both our old databases and the migrated ones all have utf8_unicode_ci as the collation set everywhere (database, tables, and columns)

I found this issue on github :

which seems germane, but I have added a parameter
collation = utf8_unicode_ci
to and I can confirm that
in our code base contains the fix which is documented in the issue.

Can anyone suggest where utf8_general_ci might be coming from?

Hi @elt,

There are several related threads to this issue; I’d like to try to draw them together over here: [OJS] Blank, white page ("Search" function)

Alec Smecher
Public Knowledge Project Team