Scrape sensor going unavailable despite template avoiding that

Configuration
1

I have a scrape sensor that takes data from my PC. I’d like the sensor to keep its last value if the PC is unreachable. I have set it up like this, but still whenever the PC goes down, the sensor becomes unavailable.

- resource: <URL here>
  method: GET
  scan_interval: 10
  sensor:
    - name: Mouse Battery
      select: "battery_percent"
      icon: mdi:mouse
      device_class: battery
      state_class: measurement
      unit_of_measurement: "%"
      value_template: "{{ value if value | is_number else this.state | default(0) }}"

Any ideas?

2

Bump! Bump.