In some scenarios, the PDFViewer does not show the correct end page in its toolbar.

I have a file with 73 pages; some of the pages have different sizes.

Current behavior: When I load the file in the PDFViewer and click the 'Last page' button, there is a slight moment where the correct page number is displayed (73), but after that it is changed to 71.

Expected behavior: The correct page number should be displayed when clicking the 'Last page' button.