skins/Vector/includes/Components/VectorComponentTableOfContents.php:73 - skins/Vector/includes/Components/VectorComponentTableOfContents.php:78

foreach ( $sections as &$section ) {
	if ( $section['is-top-level-section'] && $section['is-parent-section'] ) {
		$section['vector-button-label'] =
		$this->localizer->msg( 'vector-toc-toggle-button-label', $section['line'] )->text();
	}
}

that was moved to the component in Bug: T317900 https://gerrit.wikimedia.org/r/c/mediawiki/skins/Vector/+/867701 from skins/Vector/includes/SkinVector22.php:66 - skins/Vector/includes/SkinVector22.php:71 with virtually no changes.

foreach ( $tocData[ 'array-sections' ] as &$section ) {
	if ( $section['is-top-level-section'] && $section['is-parent-section'] ) {
		$section['vector-button-label'] =
		$this->msg( 'vector-toc-toggle-button-label', $section['line'] )->text();
	}
}

and as it shows we only add the labels for top level parents, regardless even top level parents are not being assigned since $sections is detached from the parent array Toc Data and not being assigned back in the new code.

Change 889570 had a related patch set uploaded (by Mabualruz; author: Mabualruz):

[mediawiki/skins/Vector@master] Table of contents subsection toggle buttons missing label

https://gerrit.wikimedia.org/r/889570

Change 889570 merged by jenkins-bot:

[mediawiki/skins/Vector@master] Table of contents subsection toggle buttons missing label

https://gerrit.wikimedia.org/r/889570

Test Result - Beta

Status: ✅ PASS
Environment: beta
OS: macOS Ventura
Browser: Chrome
Device: MBP
Emulated Device:NA

Test Artifact(s):

QA Steps

✅ AC1: There should be text inside the expand/collapse button element for TOC subsections.

Seems to be working now I just checked https://en.wikipedia.org/wiki/Mohamed_Salah while logged in @Edtadros Would you please recheck

cache os probably to blame here, but i am not 100% sure, since logged in users do not get cached pages, it is the only thing I can think of. So I will wait until tomorrow to be sure cache has refreshed for me on the pages on logged out cases

I can confirm there is no cache for logged in users. You can clear cache for anonymous users by appending ?action=purge to a URL.

I can confirm, as cache auto clears on Mondays that labels are showing, I will be making sure to note the purge action for future use