Reading from the source code:

https://github.com/mozilla/pdf.js/blob/57d196e3497e77c81c19f852715ce79d9fb91492/src/display/annotation_layer.js#L2846

it appears to me it was not an intention to mark downloadManager as a required parameter in AnnotationLayerParameters:

https://github.com/mozilla/pdf.js/blob/57d196e3497e77c81c19f852715ce79d9fb91492/src/display/annotation_layer.js#L63

and AnnotationLayerBuilderOptions:

https://github.com/mozilla/pdf.js/blob/57d196e3497e77c81c19f852715ce79d9fb91492/web/annotation_layer_builder.js#L40

and it should be optional, similarly to accessibilityManager for example:

https://github.com/mozilla/pdf.js/blob/57d196e3497e77c81c19f852715ce79d9fb91492/web/text_layer_builder.js#L30

**Configuration:**
- PDF.js version: 2.11.174
- Is a browser extension: no

**What is the expected behavior? (add screenshot)**

`downloadManager` to be optional

**What went wrong? (add screenshot)**

`downloadManager` marked as required

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):

let commitKey = -1;
          if (event.key === "Escape") {
            commitKey = 0;
          } else if (event.key === "Enter" && !this.data.multiLine) {
            
            
            
            commitKey = 2;
          } else if (event.key === "Tab") {
            elementData.commitKey = 3;
          }
          if (commitKey === -1) {
            return;
          }
          const { value } = event.target;
          if (elementData.lastCommittedValue === value) {
            return;
          }
          elementData.lastCommittedValue = value;
          
          elementData.userValue = value;
          this.linkService.eventBus?.dispatch("dispatcheventinsandbox", {
            source: this,
            detail: {
              id,
              name: "Keystroke",
              value,
              willCommit: true,
              commitKey,
              selStart: event.target.selectionStart,