'Failed to retrieve timescaledb version' after disabling Timescale & upgrade 5.2->6.2

[DenisBY]

A few months ago I disabled Timescale as I needed to move to RDS. Everything worked fine with Zabbix 5.2.x. Today I decided to upgrade to 6.2.6 and I'm having issues with starting the server. I logs I see "Failed to retrieve timescaledb version" however `\dx` doesn't shown anything related (and it's expected)

zabbix=> \dx
                 List of installed extensions
  Name   | Version |   Schema   |         Description          
---------+---------+------------+------------------------------
 plpgsql | 1.0     | pg_catalog | PL/pgSQL procedural language
(1 row)​

The error:

  9120:20221219:154430.063 Starting Zabbix Server. Zabbix 6.2.6 (revision 6981d8b729a).
  9120:20221219:154430.064 ****** Enabled features ******
  9120:20221219:154430.064 SNMP monitoring:           YES
  9120:20221219:154430.064 IPMI monitoring:           YES
  9120:20221219:154430.064 Web monitoring:            YES
  9120:20221219:154430.064 VMware monitoring:         YES
  9120:20221219:154430.064 SMTP authentication:       YES
  9120:20221219:154430.064 ODBC:                      YES
  9120:20221219:154430.064 SSH support:               YES
  9120:20221219:154430.064 IPv6 support:              YES
  9120:20221219:154430.064 TLS support:               YES
  9120:20221219:154430.064 ******************************
  9120:20221219:154430.064 using configuration file: /etc/zabbix/zabbix_server.conf
  9120:20221219:154430.198 Failed to retrieve timescaledb version​

[DenisBY]

I fixed it with

update config set db_extension='';

in Zabbix DB