The current system tray/app indicator system is kind of a mess.

It adds potential insecurities, and it's just generally untidy and unintuitive - will the icons be monochrome or coloured? When you click it does it open the app? Does it open a context menu? Does instead right clicking open a context menu? Does right clicking open a different context menu? For most people that stuff is minor (they're used to the jank/inconsistency of Windows, after all), but the Gnome team seems to really hate little unintuitive or inconsistency niggles like that.

They've spoken for years about wanting to create a new, standardised, cross-desktop system tray that fixes these issues, but because it requires not only cross-desktop but also third party dev collaboration, progress has been practically non-existent.

I don't know if this specific thing is related (I can't follow the link on my work PC), but if it is, it could be the first step towards the above.

E: nope, it's not that. I'm also puzzled.