I managed to fix the “Timer got out of sync” thanks to this thread. It was actually only showing up when using the frontend with an iOS device, and not related to the crashed.
But my Home Assistant instance still crash every 24 hours or so. When I add a device sending MQTT event every 10 second, it even crash faster.
Here is a graph of my CPU (green) and RAM.
It does look like a memory leak?
Is there any way I could track the component provoking it?