History crashing PC Firefox

Configuration
1

I’ve got a problem and I’m not sure how to resolve it, or prevent it.

I set up a sensor to compute an average voltage of my smart-plugs (which report their own voltages every ~20 seconds OR when there is a large swing), and added it to lovelace as a 24 hour history graph. Worked great last night when I made it.

Now this morning, it starts loading and my whole computer grinds to a stop because Firefox is using all the available CPU and I eventually have to kill everything.

So two questions:

  1. How do I remove it from lovelace in the short-term if attempting to access it crashes my browser?
  2. How do I make it not have SO many changes that it causes this problem?

Here’s the sensor that I think is causuing problems:

  - platform: min_max
    name: "L1 Voltage Avg"
    type: mean
    entity_ids:
      - sensor.s31_upstairs_radio_voltage
      - sensor.s31_kitchen_radio_voltage
      - sensor.s31_end_room_radio_voltage
      - sensor.s31_kitchen_light_voltage
      - sensor.s31_livingroom_light_voltage
      - sensor.s31_livingroom_filter_voltage
      - sensor.s31_saltwater_light_voltage
      - sensor.s31_matt_bedroom_filter_voltage
      - sensor.s31_rodi_filter_voltage

  - platform: min_max
    name: "L2 Voltage Avg"
    type: mean
    entity_ids:
      - sensor.s31_front_entry_light_voltage
      - sensor.s31_freshwater_light_voltage
      - sensor.s31_snake_light_voltage
      - sensor.s31_basement_filter_voltage

 - platform: template
    sensors:
      house_voltage_avg:
        friendly_name: "House Voltage Avg"
        unit_of_measurement: "Volts"
        value_template: "{{ (states('sensor.l1_voltage_avg') | float + states('sensor.l2_voltage_avg') | float) | round(2) }}"
        icon_template: hass:flash
2

I’ve worked around my first issue by finding a URL to a different “tab” that didn’t load the sensor with huge history and then doing raw-edit to remove the problem-sensor

So how do I avoid this in the future?