Add labels to gallery thumbnail size controls

[whitewooood]

Summary

• add accessible labels to the gallery thumbnail size decrease button, range control, and increase button
• route those labels through gallery content config with default fallbacks
• add locale entries for supported locale files and a puppeteer regression test

Fixes #1488.

Validation

• npm run build
• CI=true npm test -- tests/test.js -t "labels gallery thumbnail size controls" --runInBand
• npx prettier --check tests/test.js src/content-handlers/iiif/modules/uv-shared-module/GalleryComponent.ts src/content-handlers/iiif/extensions/config/ContentLeftPanel.ts src/content-handlers/iiif/extensions/uv-openseadragon-extension/config/Config.ts src/content-handlers/iiif/extensions/uv-av-extension/config/config.json src/content-handlers/iiif/extensions/uv-openseadragon-extension/config/config.json src/locales/cy-GB.json src/locales/en-GB.json src/locales/fr-FR.json src/locales/pl-PL.json src/locales/sv-SE.json
• npx eslint tests/test.js src/content-handlers/iiif/modules/uv-shared-module/GalleryComponent.ts src/content-handlers/iiif/extensions/config/ContentLeftPanel.ts src/content-handlers/iiif/extensions/uv-openseadragon-extension/config/Config.ts
• npm run build-tsc
• npm run checkLocaleUsage
• npm run findMissingTranslations (reports pre-existing missing keys for adjust image labels; no new thumbnail-size keys missing)
• CI=true npm test -- --runInBand (first run had a transient thumbnail image load failure; the failing test passed when rerun directly, and the full suite passed on rerun: 4 passed, 1 skipped)

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Project	Deployment	Actions	Updated (UTC)
universalviewer	Ready	Preview, Comment	Jun 22, 2026 3:02pm

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[demiankatz]

Thanks for your contribution, @whitewooood -- I took a quick look and have a question and suggestion below.

[demiankatz]

Where/how did you source your non-English translations? Do we need to have our translation team review them for accuracy?

[LlGC-szw]

I've reviewed the cy-GB translations and am happy that they are correct @demiankatz @erinburnand @LanieOkorodudu .

[erinburnand]

French translations have been approved @demiankatz @LanieOkorodudu

[erinburnand]

Polish translations also reviewed and approved @demiankatz @LanieOkorodudu

[demiankatz]

If I'm keeping track correctly, that just leaves Swedish in need of approval -- is there someone working on that?

[LanieOkorodudu]

It might be worth asking the SNA team to take a look if they have the time.

[erinburnand]

I tagged Linea in the Slack message, I assume she hasn't had time yet?

[whitewooood]

Thanks for the review. I pushed an update using more specific content keys: decreaseThumbnailSize, thumbnailSize, and increaseThumbnailSize.

For the non-English strings, I added direct equivalents so the new labels resolve in the existing locale files. They have not gone through a separate translation-team review, so adjustments from the translation workflow would be welcome.

[demiankatz]

Thanks, @whitewooood, I have put this in the "in testing" column of the Community Board so we can discuss it at a future Community Call and figure out the best way to get all the translations reviewed.

[LanieOkorodudu]

@demiankatz, I tested this and I can confirm the aria-label has been added. Just wondering, are we all happy with how it's translated in the supported locales?

[demiankatz]

Thanks, @LanieOkorodudu, I posted on the #translations channel of Slack on June 22 asking the translation team to review this, but nobody has replied to me. Maybe it's worth following up. Would someone at the BL be willing to try, since I'll be away for the coming week?