Have you read the Contributing Guidelines on issues?

• I have read the Contributing Guidelines on issues.

Prerequisites

• I'm using the latest version of Docusaurus.
• I have tried the npm run clear or yarn clear command.
• I have tried rm -rf node_modules yarn.lock package-lock.json and re-installing packages.
• I have tried creating a repro with https://new.docusaurus.io.
• I have read the console error message carefully (if applicable).

Description

getSidebarTranslationFileContent in packages/docusaurus-plugin-content-docs/src/translations.ts
generates translation keys for category generated-index links using category.key ?? category.label
(lines 96, 109, 118).

But transformSidebarCategoryLink in the same file looks up those translations using only
category.label (lines 182, 186), ignoring the key attribute entirely.

Line 200 in the same translateSidebar function already correctly uses item.key ?? item.label for
category label lookups. Same for links (line 210) and docs (line 219). Only
transformSidebarCategoryLink was missed.

Related: #8118

Reproducible demo

No response

Steps to reproduce

1. Create a sidebar category with a custom key attribute in _category_.json
2. Give that category a generated-index link with a title and description
3. Run docusaurus write-translations to generate the translation file
4. Translate the generated-index title and description entries in the translation file
5. Build the site with the target locale

Expected behavior

The generated-index page title and description resolve from the translation file using the key sidebar <name>.category.<key>.link.generated-index.title.

Actual behavior

The generated-index page title and description remain untranslated because transformSidebarCategoryLink looks up sidebar.<name>.category.<label>.link.generated-index.title while the translation file contains sidebar.<name>.category.<key>.link.generated-index.title.

Your environment

• Public source code:
• Public site URL:
• Docusaurus version used:
• Environment name and version (e.g. Chrome 89, Node.js 16.4):
• Operating system and version (e.g. Ubuntu 20.04.2 LTS):

Self-service

• I'd be willing to fix this bug myself.