**Problem 1:**
The new `mul` language code functionality depends on pre-existing handling of languages (e.ga reliable language fallback chain. babelsSo far, the Mobile version seems to follow a different language fallback chain).n than we follow on Desktop:
In mMobile termbox, the languages listed are currently mostly hardcoded:e IP experience
* Heading: English (for IPs),likely uselang (if logged-ing, or set via uselang=)but cannot be changed) *without* language fallback
* In more languages: Selected languages based on visitor’s geographical information (see T323098#8402520English (in the heading), German, French, Bavarian (unclear where this comes from, it is different to desktop)
* All entered languages: All entered languages
* https://m.wikidata.org/wiki/Q444444?uselang=en-gb (please log out)
**Example:**Desktop IP experience
* Heading: Uselang (can be changed) *with* language fallback
* In more languages: English, German, Uselang, Russian (unclear where this comes from, it is different to mobile)
* https://m.wikidata.org/wiki/Q3128515* All entered languages: All entered languages
* https://mwww.wikidata.org/wiki/Q3128515444444?uselang=en-gb (please log out)
**Notes:**Mobile logged-in experience
* Heading: uselang (can also be set via uselang=) *without* language fallback
* In more languages: 1. Uselang (in the heading), 2. Based on Babels
* Babels are currently not taken into account [WRONG, THEY ARE -> needs to be rewritten]* All entered languages: All entered languages
* https://m.wikidata.org/wiki/Q444444?uselang=en-gb (please log in)
**Acceptance criteria:**Desktop logged-in experience
* Heading: uselang (can also be set via uselang=) *with* language fallback
* In more languages: 1. Uselang, 2. Based on Babels
[] We understand the status quo.* All entered languages: All entered languages
* https://www.wikidata.org/wiki/Q444444?uselang=en-gb (please log in)
**Problem 2:**
[] We understand how hard will it be to implement handling of languages to the point we currently have on desktop (e.g. babels, fallback chain) (at least one possible option forward is described and roughly estimated, or if describing options forward is out of scopeIf you edit using the mobile termbox, explain what is needed to get to options forward)you can edit the heading directly.
**Original:**{F35816343}
This workflow makes the mobile termbox incompatible with language fallback.
To enable language fallback on the mobile termbox, we would need to modify the editing workflow. It is currently unclear to us, how much of that work would survive a later refactoring of the front end (to make full use of the new design system). This information would help us to better plan what changes we want to make now and what changes we can make at a later point in time (with greater overall effectiveness).
**Acceptance criteria:**
Problem 1:
[] We understand where the differences between Mobile and Desktop come from.
[] We understand what will be needed to make the Mobile language fallback the same as on the Desktop.
Problems 1 & 2:
[] We understand, how much of the work is still useful after we replace the frontend (in favor of a new design system-powered version).