1.21 release notes

Nutrient Web SDK 1.21 finishes the localization of the viewer: Every UI string now renders translated in all 32 locales, the component library’s strings became overridable, and right-to-left layout is applied for regional Arabic and Hebrew locales. It also records who created an annotation or comment, adds print-production rendering controls for overprinting and 100 percent K black, surfaces terminal page render failures through a new page.renderError event, and extends template population to XLSX and PPTX. See the changelog for full details.

Renamed message placeholders

Five messages had their named placeholders renamed to the positional {arg0} form. If you override any of these keys through NutrientViewer.I18n.messages, update your translation to use the new placeholder — a translation that still uses the old name renders the placeholder as literal text.

NutrientViewer.load({
  // Before: named placeholder.
  // I18n: { messages: { en: { searchDocumentDescription: "Type at least {min} characters" } } }

  // After: positional placeholder.
  I18n: {
    messages: {
      en: { searchDocumentDescription: "Type at least {arg0} characters" },
    },
  },
});

Only these five keys changed. Every other overridden message keeps its placeholders.

Complete UI localization

Parts of the interface — the comment editor toolbar among them — previously rendered in English in every non-English locale. Those strings are now translated across all 32 locales, along with the annotation blend mode labels in Thai and the Screen blend mode in Arabic. The English wording of several strings was corrected in the process, so a few labels changed: For example, the custom color dialog is now titled “New Color.”

The component library’s strings are now part of the SDK’s message catalog, which means they carry message IDs and can be customized through NutrientViewer.I18n.messages like any other string. For the full list of IDs, their English text, and the surface each one appears on, refer to the localization guide in the API reference.

A translation that can’t be formatted — because of invalid ICU MessageFormat syntax, for example — is ignored and the English text is used, as before. It now also logs a console warning naming the message key, the locale, and the formatter error, so a broken override is visible instead of silently falling back.

Right-to-left layout for regional locales

The UI now switches to a right-to-left layout whenever the active language is Arabic or Hebrew, not only for the exact ar and he tags. This covers three cases that previously stayed left-to-right: a regional locale such as ar-EG, a browser language of Arabic or Hebrew when no locale is configured, and a locale changed after load with setLocale().

Annotation and comment attribution

Annotation.createdBy and Comment.createdBy expose the user ID of the authenticated user that created the record:

const annotations = await instance.getAnnotations(0);
annotations.forEach((annotation) => {
  console.log(annotation.createdBy);
});

Both properties are read-only and assigned by the backend — a locally set value is never sent. They’re available on server-backed deployments only, and are null for records created without an authenticated user, or when the server holds an author it can no longer resolve to an upstream user ID. Annotation.createdBy requires Instant synchronization against Document Engine 1.18.0 or later.

Print-production rendering

Two configuration options control rendering fidelity for prepress and soft-proofing workflows. Documents that don’t use CMYK color or overprinting are unaffected by either option.

NutrientViewer.load({
  overprintPreview: NutrientViewer.OverprintPreview.OFF,
  blackRendering: NutrientViewer.BlackRendering.PURE_BLACK,
  // ...
});

• overprintPreview controls whether the renderer simulates the overprinting a document uses, where overlapping inks print on top of each other instead of knocking each other out. It defaults to AUTO, which simulates overprinting when the document uses it; OFF disables the simulation.
• blackRendering controls how exact 100 percent K-only CMYK black is rendered. It defaults to ACCURATE, which renders it as the dark charcoal Acrobat shows on screen; PURE_BLACK maps it to #000000 instead, which some print workflows prefer for checking black-only content.

In server-backed mode, both options require Document Engine 1.18.0 or later and are ignored by older servers.

Terminal page render failures

A page render that exhausts WebAssembly memory is retried once. When the retry also fails, the SDK now displays a localized page-level error and emits page.renderError, so your application can react instead of leaving the user with a blank page:

instance.addEventListener("page.renderError", (event) => {
  if (event.error instanceof NutrientViewer.OutOfMemoryError) {
    console.log(event.pageIndex, event.pageStillDisplaysContent);
  }
});

pageStillDisplaysContent reports whether the page is still showing earlier, lower-resolution content when the event is emitted. The device itself can still have free memory — the failure is specific to the WebAssembly heap.

XLSX and PPTX template population

populateDocumentTemplate() now accepts XLSX and PPTX templates in addition to DOCX, and it returns the populated file as an ArrayBuffer.

XLSX templates process every worksheet and support placeholders, conditions, row loops, images, and typed number, date, percentage, and Boolean cells. Column loops and list expansion within a single cell aren’t supported, and formula references, structured table ranges, and defined names aren’t adjusted when row loops insert rows. PPTX templates support placeholders, loops, conditions, tables, and images on slides; slide masters, slide layouts, and speaker notes aren’t processed.

Other additions

• The API reference ships a localization guide listing the locales the SDK provides catalogs for and every overridable message ID.
• setLocale() and preloadLocalizationData() throw a clearer error when a locale can’t be loaded and expose the underlying failure as error.cause.
• AI Assistant agent skills now require a description, which the agent uses to decide when to apply each skill.
• Dark-color fidelity of Multiply and related blend modes in CMYK transparency groups is improved by blending in the group’s color space.

Rendering

• Fixes non-isolated transparency groups compositing their backdrop twice, which rendered blended content too dark or washed out.
• Fixes missing page content when rendering PDFs with certain inline images.
• Fixes missing CJK text and incorrect Yen symbols in PDFs that use configured font substitutions.
• Fixes the black box of an applied redaction being misplaced and incorrectly sized when the redacted content sits inside a transformed form XObject.
• Fixes layer visibility changes through setLayersVisibilityState() or the layers sidebar hiding content in optional content groups that getLayers() doesn’t expose, such as page-level OCGs in CAD documents. These groups now keep the document’s native visibility.
• Fixes slow saving of free text annotations containing emojis.

Forms and document editing

• Fixes text form fields rejecting all input when their JavaScript Keystroke script calls AFMergeChange or AFExtractNums.
• Fixes editing a radio button option in Form Creator moving the group’s option values onto the wrong widgets when the document was exported.
• Fixes applyRedactions() being skipped when batched with page move or removal operations.
• Fixes keyboard page reordering in the Document Editor losing its drop position when the interface updates mid-drag.

Collaboration

• Fixes a comment edit being silently dropped when it was made in the brief window between the comment’s create request being sent and the server’s acceptance of it.
• Fixes an unsaved comment draft carrying over into another comment thread when switching between threads.

User interface and accessibility

• Fixes the measurement scale target unit picker announcing the source unit picker’s label to screen readers.
• Fixes Japanese and Korean UI strings that displayed stray characters instead of a value, dropped the unit after a point size, or reversed the two numbers in “N of M” counters such as the search result position.
• Fixes translations in Czech, Slovak, and Dutch that rendered a raw placeholder or failed to render, affecting the comment count, the comment thread label, and the duplicate form field name error.

Loading, platform, and API reference

• Fixes a Content Security Policy violation reported on every load when using the recommended script-src 'self' 'wasm-unsafe-eval' policy.
• Fixes the import of annotation and action JSON whose numeric fields aren’t finite numbers, which previously produced annotations that render incorrectly.
• Fixes the missing Serializers.BookmarkJSON properties in the API reference.

For a full list of fixes, refer to the changelog.

For a complete list of changes, bug fixes, and improvements, refer to the changelog. For previous release notes, refer to the Web SDK 1.20 release notes. We appreciate your feedback and contributions as we continue to enhance Nutrient Web SDK.