Careful testing is required to assess that all site features still work in acceptable way.

@Nikerabbit: Do you test it or shall I do something? If latter, what exactly?

I currently don't have time for a testing project this large.

And how can I help you?

Please how can this be looked into again?

In T170264#4270841, @Ammarpad wrote:

Please how can this be looked into again?

MobileFrontend is a complex extension. Have you considered other mobile-friendly skins? For instance, you could try Timeless and let us know how it works for you with Translate:
https://translatewiki.net/wiki/special:Translate?useskin=timeless

MobileFrontend is not a bad idea: Timeless may be as convenient on mobile as MinervaNeue, but it’s less convenient on desktop as Vector. MF makes it possible to use two completely different skins on mobile and desktop. (Also, Timeless has a slightly larger padding on Special:Translate than MinervaNeue, at least on Meta.)

If turning on MobileFrontend for everyone is too risky, is it possible to make it opt-in using a preference or by making it a beta feature?

I've not suggested to enable Timeless for desktop.

MobileFrontend is hardly the cleanest way to have different defaults for desktop and mobile, if that's what you're suggesting.

As a user I don’t know about any way to have different skins permanently set on mobile and on desktop.

I’ve played a bit with Timeless on mobile, and some pages like the preferences are quite hard to use on a small screen. MobileFrontend does a good job in simplifying things so that they work on narrow screens.

In T170264#4273048, @Tacsipacsi wrote:

As a user I don’t know about any way to have different skins permanently set on mobile and on desktop.

You can select your default skin in your preferences: https://translatewiki.net/wiki/Special:Preferences#mw-prefsection-rendering

In T170264#4272913, @Tacsipacsi wrote:

MobileFrontend is not a bad idea: Timeless may be as convenient on mobile as MinervaNeue, but it’s less convenient on desktop as Vector. MF makes it possible to use two completely different skins on mobile and desktop. (Also, Timeless has a slightly larger padding on Special:Translate than MinervaNeue, at least on Meta.)

If you have found bugs or have feature requests for Timeless, please open a task :)

In T170264#4277089, @Framawiki wrote:

In T170264#4273048, @Tacsipacsi wrote:

As a user I don’t know about any way to have different skins permanently set on mobile and on desktop.

You can select your default skin in your preferences: https://translatewiki.net/wiki/Special:Preferences#mw-prefsection-rendering

I know how to select the default skin. The problem is that I can select either Timeless or Vector, and there is no way to set it to use one skin on mobile, and another on desktop.

I'm wondering if this is a relevant direction to go anymore. It seems skins are becoming responsible and MobileFrontend isn't necessarily needed.

Indeed many things are being moved from MobileFrontend to core or Minerva. However, I don’t know about any plans to move the feature because of which I proposed installing MobileFrontend (automatically switch to Minerva on mobile without having to change the desktop skin) out of MobileFrontend.