Without changing anything on my side, now the topic titles (at least in Site Feedback) displays in Grey and White now, in Chrome, Firefox and Vivaldi.
I’ve activated this plug-ins again, and keep sync the desktop version with the mobile version since the plug-ins has review by the Discourse TEAM recently and adapted to the new core changed…
I’ve tested in a custom theme in mobile browser and a mobile browser itself…
Mobile OP avatars
A Discourse theme component that forces the original poster’s avatar to show in the topic list on mobile devices, rather than the latest poster.
Regards.,