fix: x-axis annotations missing on line/area/scatter charts (5.10.4 regression)

[Copilot]

In 5.10.4, a type-safety change in getStringX() broke x-axis annotations on line, area, and scatter charts that use simple array series data — annotations were silently not rendered.

Root cause

Config.js automatically sets convertedCatToNumeric = true for line/area/scatter charts. This causes _generateExternalLabels to produce numeric categoryLabels (e.g. [1, 2, 3, 4, 5] via the default Math.floor formatter). The 5.10.4 change converted the search value to a string before the indexOf lookup:

// 5.10.4 — broken: searches for '2' in [1, 2, 3, 4, 5] → -1
x = w.labelData.categoryLabels.indexOf(String(x)) + 1

indexOf('2') returns -1 in a number array, so the annotation position resolves to index 0, the DOM lookup fails, and getStringX returns the raw annotation value (e.g. 2) as a pixel offset — placing the line at the far left edge or causing it to be clipped entirely.

Fix

Convert both sides to strings before comparing, which correctly handles all type combinations (number labels + number x, string labels + string x, cross-type):

// src/modules/annotations/Helpers.js
const strX = String(x)
x = w.labelData.categoryLabels.findIndex(
  (l) => String(l) === strX,
) + 1

Test

Added a regression test verifying that an xaxis annotation with a numeric x value renders on a line chart with simple array data.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• jsfiddle.net
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If you need me to access, download, or install something from one of these locations, you can either:

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