GUI is hanging

Hello everyone,
I started with FHEM over 10 years ago. In the meantime, I wanted to switch to ioBroker, but never finished. Now I have decided to move everything to Homeassistant. Well, except for Siemens PLC S7, there is no integration for that.

But now I have a sporadic error. Often (1-2x per minute) the interface does not respond and I have to reload it. Mostly you have the turning circle or commands on click in a Dashboard are not working.
In the Mosquitto log I have seen that there are always reconnects from Zigbee2MQTT. Both are running as add-ons, but I didn’t know if that is the reason for blocking.
But I don’t notice anything else. Do you have any ideas where I can look further?

Extract from the log:

2024-01-25 13:20:00: New connection from 172.30.32.2:56680 on port 1883.
2024-01-25 13:20:00: Client <unknown> closed its connection.
2024-01-25 13:22:00: New connection from 172.30.32.2:51362 on port 1883.
2024-01-25 13:22:00: Client <unknown> closed its connection.
2024-01-25 13:24:00: New connection from 172.30.32.2:36418 on port 1883.
2024-01-25 13:24:00: Client <unknown> closed its connection.