webserver: errors in browser console

[M95D]

The problem

I noticed errors in the browser console. Browsers used: Firefox and Edge.
Except for the Cover component name bug that I reported earlier, I didn't notice other broken features, but who knows, I'm no expert.

webserver v1:

content.js:155
 Uncaught TypeError: Cannot read properties of undefined (reading 'demodal')
    at content.js:155:72
    at Array.every (<anonymous>)
    at content.js:155:43
    at Array.every (<anonymous>)
    at MutationObserver.<anonymous> (content.js:154:19)
(anonymous)     @       content.js:155
(anonymous)     @       content.js:155
(anonymous)     @       content.js:154
childList
(anonymous)     @       webserver-v1.min.js:1

webserver v2:

www.js:3
 Uncaught (in promise) Error: invalid template strings array
kt      @       www.js:3
Mt      @       www.js:3
N       @       www.js:3
_$AC    @       www.js:3
g       @       www.js:3
_$AI    @       www.js:3
Vt      @       www.js:3
update  @       www.js:3
performUpdate   @       www.js:1
scheduleUpdate  @       www.js:1
_$Ej    @       www.js:1
await in _$Ej
requestUpdate   @       www.js:1
_$Eu    @       www.js:1
E       @       www.js:1
f       @       www.js:3
bt      @       www.js:28
u       @       www.js:3
g       @       www.js:3
_$AI    @       www.js:3
Vt      @       www.js:3
update  @       www.js:3
performUpdate   @       www.js:1
scheduleUpdate  @       www.js:1
_$Ej    @       www.js:1
await in _$Ej
requestUpdate   @       www.js:1
_$Eu    @       www.js:1
E       @       www.js:1
f       @       www.js:3
R       @       www.js:28
(anonymous)     @       www.js:3
(anonymous)     @       www.js:3
V       @       www.js:28
(anonymous)     @       www.js:28

webserver v3:

www.js:3
 Uncaught (in promise) Error: invalid template strings array
Ho      @       www.js:3
na      @       www.js:3
we      @       www.js:3
_$AC    @       www.js:3
g       @       www.js:3
_$AI    @       www.js:3
ha      @       www.js:3
update  @       www.js:3
performUpdate   @       www.js:1
scheduleUpdate  @       www.js:1
_$Ej    @       www.js:1
await in _$Ej
requestUpdate   @       www.js:1
_$Eu    @       www.js:1
Vt      @       www.js:1
J       @       www.js:3
Ro      @       www.js:34
u       @       www.js:3
g       @       www.js:3
_$AI    @       www.js:3
ha      @       www.js:3
update  @       www.js:3
performUpdate   @       www.js:1
scheduleUpdate  @       www.js:1
_$Ej    @       www.js:1
await in _$Ej
requestUpdate   @       www.js:1
_$Eu    @       www.js:1
Vt      @       www.js:1
J       @       www.js:3
Lt      @       www.js:34
(anonymous)     @       www.js:3
(anonymous)     @       www.js:3
te      @       www.js:34
(anonymous)     @       www.js:34

Which version of ESPHome has the issue?

2025.6.0

What type of installation are you using?

pip

What platform are you using?

ESP8266

Component causing the issue

webserver

YAML Config

esp32:
  board: m5stick-c

esphome:
  name: test-web

wifi:
[...]

api:
  port: 10098
  reboot_timeout: 0s

mdns:
  disabled: true

web_server:
  port: 80
  version: 2
  ota: false

cover:
  - platform: time_based
    device_class: shade
    id: "C1"
    name: "Shades Bedroom Left"
    open_action:
      switch.turn_off: R1
    close_action:
      switch.turn_on: R1
    stop_action:
      switch.turn_on: R1S
    open_duration: 20s
    close_duration: 20s
    has_built_in_endstop: true

remote_transmitter:
  pin: GPIO32
  carrier_duty_percent: 100%

substitutions:
  #ID: "<-- address ---------------><ch><-cmnd->"
  R1U: "0011001100100000110101011010000100010001"
  R1D: "0011001100100000110101011010000100110011"
  R1S: "0011001100100000110101011010000101010101"

switch:

  - platform: template
    id: R1
    name: "BedRoom 1"
    internal: true
    assumed_state: true
    optimistic: true
    restore_mode: DISABLED
    turn_off_action:
      remote_transmitter.transmit_rc_switch_raw:
        code: $R1U
        protocol: &Proto
          pulse_length: 357
          sync: [14,2]
          one:   [2,1]
          zero:  [1,2]
        repeat: &Repeat
         times: 2
         wait_time: 200ms
    turn_on_action:
      remote_transmitter.transmit_rc_switch_raw:
        code: $R1D
        protocol: *Proto
        repeat: *Repeat

Anything in the logs that might be useful for us?

Additional information

No response