H1 in the color theme editor lacks contrast

The H1 in the iframe to preview theme does not have enough contrast.

WCAG warnings in the test class [org.xwiki.flamingo.test.ui.FlamingoThemeIT]:
Validation in the test method [validateColorThemeFeatures]
Check for [org.xwiki.test.ui.po.ViewPage] at http://xwikiweb:8080/xwiki/bin/view/FlamingoThemes/validateColorThemeFeatures.
Found [3] items

1: Elements must have sufficient color contrast
Description: Ensures the contrast between foreground and background colors meets WCAG 2 AA contrast ratio thresholds
Help URL: https://dequeuniversity.com/rules/axe/4.6/color-contrast?application=axeAPI
Help: Elements must have sufficient color contrast
Impact: serious
Tags: cat.color, wcag2aa, wcag143, ACT

HTML element:
<h1>Main</h1>
Selector: iframe, h1
Fix any of the following:
Element has insufficient color contrast of 2.14 (foreground color: #0000ff, background color: #ff0000, font size: 25.5pt (34px), font weight: normal). Expected contrast ratio of 3:1