Background is already set on the outer <figure>-element:

figure[typeof~='mw:File/Thumb'],
figure[typeof~='mw:File/Frame'] {
 border:var(--border-subtle,1px solid #c8ccd1);
 border-bottom:0;
 background-color:var(--background-color-interactive-subtle,#f8f9fa);
}

I don't see any reason why the same background is set again on the <img>:

figure[typeof~="mw:File/Thumb"] > :not(figcaption) .mw-file-element, 
figure[typeof~="mw:File/Frame"] > :not(figcaption) .mw-file-element {
	[...]
	background: var(--background-color-interactive-subtle,#f8f9fa);
}

Removing that line would solve this issue, as .skin-invert-image won't invert anything that is defined outside the <img>.

(Code according to Firefox DevTools; don't know where to find it in the repo.)

It works fine with Minerva, this problem only concerns Vector 2022

Do you have an estimate of when this will be resolved? Given the imminent night mode, onwiki documentation needs to be drawn up for contributors. It would be useful to have the class up and running to explain how it works.

I agree, this seems essential for the further roll-out of the dark mode.

Change #1051491 had a related patch set uploaded (by Stoyofuku-wmf; author: Stoyofuku-wmf):

[mediawiki/core@master] [Figures] Remove redundant background color interfering with invert

https://gerrit.wikimedia.org/r/1051491

Change #1051491 merged by jenkins-bot:

[mediawiki/core@master] [Figures] Remove redundant background color interfering with invert

https://gerrit.wikimedia.org/r/1051491

@Jdlrobson It's dark but you can't see much of it, as seen in the screenshot.

Test Result - Beta

Status: ❌ FAIL
Environment: Beta
OS: macOS Sonoma 14.5
Browser: Chrome 126
Device: MBA
Emulated Device: NA

Test Artifact(s):

Test Steps

1. Visit https://fr.wikipedia.org/wiki/Torchage_du_gaz_naturel#Aspects_techniques

Lines are dark

Hi @GMikesell-WMF the screenshot and URL appears to b beta and this change is going out with MW-1.43-notes (1.43.0-wmf.13; 2024-07-09) ?
Please repeat the test on https://en.wikipedia.beta.wmflabs.org/wiki/T367589

Test Result - Beta

Status: ✅ PASS
Environment: Beta
OS: macOS Sonoma 14.5
Browser: Chrome 126
Device: MBA
Emulated Device: NA

Test Artifact(s):

Test Steps

1. Visit https://en.wikipedia.beta.wmflabs.org/wiki/T367589

Lines are dark

@Jdlrobson Please review below, thanks!

Test Result - PROD

Status: ❌ FAIL
Environment: PROD
OS: macOS Sonoma 14.5
Browser: Chrome 126
Device: MBA
Emulated Device: NA

Test Artifact(s):

Test Steps

1. Visit https://en.wikipedia.org/wiki/Gas_flare

PROD has a grey background, the same as the light version. It doesn't look like Beta.

PROD	Beta

Ah they updated the image :/

@GMikesell-WMF does https://fr.wikipedia.org/wiki/Torchage_du_gaz_naturel#Aspects_techniques work?

@SToyofuku-WMF Thanks for the update as seen in the screenshot below! I will move this as Pass, thanks!

https://fr.wikipedia.org/wiki/Torchage_du_gaz_naturel#Aspects_techniques?vectornightmode=1