Translations for MultiMC

To participate in the translation effort, go to the MultiMC crowdin site and join the project and get in touch on discord. (If you don't have a Crowdin account, you can create one using your Facebook, Google, Twitter, Github, GitLab or any other email.)

You may want to use POEdit to work on the translations. MultiMC allows putting a .po file in the translations folder and see changes in the application as you translate. Combined with its Crowdin integration, this is pretty powerful and comfortable to use.

Some setup is required to add completely new translations, so please get in touch.

Tooling

update.py regenerates template.pot from the Launcher source (checked out to src/). release.py turns the .po files into the .qm files and index_v2.json the Launcher downloads (into build/). Both run in the multimc/toolchains/translations image (Qt 5.15.2 linguist tools, gettext, python3), defined in the MultiMC Toolchains repository, whose automation runs them (releases on every push to master, template updates on request). Each script's --help describes it.

• Extraction needs Qt 5.15's lupdate: Qt 5.6's stops parsing a file at the first C++11 raw string literal and silently misses the strings after it. update.py refuses other versions, fails if a source type it doesn't scan uses tr(), and prints which strings were added or removed. It hands the source files to lupdate in sorted order: the order of the entries in template.pot follows it, so the template no longer depends on how the filesystem lists directories (the old update.sh did, so its first template from update.py reorders entries once, with no string changes).
• One <lang>.qm per language; index_v2.json names it and gives its SHA-1, which the Launcher checks. Until 2026-10 every release also wrote a <sha1>.class copy (a name Cloudflare once cached for free), so a set of files piled up with every release; the names are fixed now, and the publish keeps only the current files.
• .qm files from Qt 5.15's lrelease only add a language tag, which the Qt 5.6 runtime skips; they load and translate the same.
• validate_po.py checks each translation with msgfmt -c. release.py drops broken entries (mismatched newlines, missing %1 placeholders, ...) so they show in English, and releases the rest. A language that can't be repaired keeps its previous release: its entry is copied from the previous index_v2.json (--previous-index, a file or URL; default the live one); if that can't be loaded, the release fails rather than drop the language. The pull request check runs the same validator and lists what would be dropped.

Qt's own strings

Qt's built-in dialogs, standard buttons and context menus (OK/Cancel, Copy/Paste, the file dialog, wizard buttons, the macOS application menu...) have their own strings. qt_strings.py collects the ones the Launcher shows into qt.pot, so they can be translated here like ours, and writes qt/<lang>.po pre-filled with Qt's own translations where the Qt project has one.

python3 qt_strings.py    # in the translations tools image

It downloads the pinned qttranslations source packages of the Qt versions we ship (5.15.2 and 5.6.3, checked by SHA-256) into .qt-sources/. The output is deterministic. The list of Qt contexts and the language mapping are at the top of the script. Rerun it when either changes, or when moving to another Qt version.

crowdin.yml sends qt.pot to Crowdin as its own file, labelled qt-builtin. release.py merges each qt/<lang>.po into that language's .qm, so the Launcher needs no changes; the translated/untranslated counts in index_v2.json still only count MultiMC's own strings. A broken qt/<lang>.po is left out and the language ships without Qt's strings.