drawcustom: y coordinate stripped from payload elements in HA service call UI

[SyFode]

Bug Description

When using the opendisplay.drawcustom service through Home Assistant's Developer Tools → Actions UI (YAML mode), the y coordinate key is silently stripped from payload elements. All text and other elements that use y for vertical positioning auto-stack from the top instead of appearing at their specified y coordinates.

Steps to Reproduce

1. Go to Developer Tools → Actions → opendisplay.drawcustom
2. Enter YAML with a payload containing text elements with explicit y values:

service: opendisplay.drawcustom
data:
  device_id: <device_id>
  background: white
  rotate: 0
  dither: burkes
  refresh_type: full
  payload:
    - type: text
      value: "y=10"
      x: 10
      y: 10
      size: 32
    - type: text
      value: "y=250"
      x: 10
      y: 250
      size: 32
    - type: text
      value: "y=400"
      x: 10
      y: 400
      size: 32

3. All three text lines appear stacked from the top of the display, ignoring the y values.
4. The HA log shows: Element X: circle requires: y — confirming y is missing from the element dict when it reaches odl_renderer.

Workaround

Calling the same service via the HA REST API with JSON payload works correctly:

curl -X POST "http://HA_HOST:8123/api/services/opendisplay/drawcustom" \
  -H "Authorization: Bearer TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"device_id":["ID"],"payload":[{"type":"text","value":"y=10","x":10,"y":10,"size":32},{"type":"text","value":"y=250","x":10,"y":250,"size":32}],"background":"white","rotate":0,"dither":"burkes","refresh_type":"full"}'

Via REST API, text appears at the correct y coordinates.

Analysis

The payload field uses selector: object in services.yaml. When HA processes the YAML service call through its UI, the y key appears to be stripped from the dict items within the payload list. The x key works fine, and shape-specific coordinates (x_start, y_start, x_end, y_end) also work. Only y (a short single-letter key) is affected.

This may be related to YAML 1.1 (PyYAML) parsing where y is treated as a boolean true value, or it may be a HA selector: object schema processing issue.

Environment

• HA version: 2026.8.1
• Integration version: 3.0.0-beta.10
• Device: Seeed Studio XIAO 7.5" BW (ESP32-C3)
• Firmware: 2.26.2

[mbresch]

Same behavior in my environment:

• HA version: 2026.8.1
• Integration version: 3.0.0-beta.10
• Devices: Waveshare ESP32 Display Board (waveshare cloud module 19399) and Seeed reTerminal E1001
• Firmware: 2.26.2

[Ulli2k]

I have a very similar issue.
I can set from HA all types except Icon.
If i want to define a icon I get an error that y value ist missing.
So...stripped off.

HA version: 2026.8.1
Integration version: 3.0.0-beta.10
Devices: Seeed 7.5 diy
Firmware: 2.26.2