Fix (beta): prevent pdfjs offsetParent warning (#13197)

src-ui/src/app/components/common/pdf-viewer/pdf-viewer.component.spec.ts

@@ -138,6 +138,18 @@ describe('PngxPdfViewerComponent', () => {
     expect(applyScaleSpy).toHaveBeenCalled()
   })
 
+  it('does not reset the viewer when it is already on the requested page', async () => {
+    await initComponent()
+
+    const viewer = (component as any).pdfViewer as PDFViewer
+    const currentPageSpy = jest.spyOn(viewer, 'currentPageNumber', 'set')
+    component.page = viewer.currentPageNumber
+
+    ;(component as any).applyViewerState()
+
+    expect(currentPageSpy).not.toHaveBeenCalled()
+  })
+
   it('dispatches find when search query changes after render', async () => {
     await initComponent()
 

src-ui/src/app/components/common/pdf-viewer/pdf-viewer.component.ts

@@ -256,7 +256,9 @@ export class PngxPdfViewerComponent
         Math.max(Math.trunc(this.page), 1),
         this.pdfViewer.pagesCount
       )
-      this.pdfViewer.currentPageNumber = nextPage
+      if (nextPage !== this.pdfViewer.currentPageNumber) {
+        this.pdfViewer.currentPageNumber = nextPage
+      }
     }
     if (this.page === this.lastViewerPage) {
       this.lastViewerPage = undefined