Admin Navigation Panel excluded page 'None' lacks contrast

Admin only

WCAG warnings in the test class [org.xwiki.panels.test.ui.docker.AllIT]:
Validation in the test method [navigationPanelAdministration]
Check for [org.xwiki.panels.test.po.NavigationPanelAdministrationPage] at http://xwikiweb:8080/xwiki/bin/admin/XWiki/XWikiPreferences?form_token=PEoBFTUzHl49EBE6kjM7DQ&editor=globaladmin&forceEdit=true&section=panels.navigation&force=true&.
Found [2] items
2: 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:
<li class="empty">
None
<input type="hidden" name="PanelsCode.NavigationConfigurationClass_0_exclusions" value="">
</li>
Selector: [.otherPages > .exclusion-filter-pages > .empty]
Fix any of the following:
Element has insufficient color contrast of 2.84 (foreground color: #999999, background color: #ffffff, font size: 10.5pt (14px), font weight: normal). Expected contrast ratio of 4.5:1