Yes, indeed, changing the window size refreshes the window and the PDF content is displayed. However, at least in my case the problem seems not to be limited to 'when the window opens maximized'. Also (to Pedro): my initial description may have been confusing, but the problem is NOT related to a specific PDF file. As far as I can tell it happens with any file. It is therefore useless to attach a PDF file.
Yes, indeed, changing the window size refreshes the window and the PDF content is displayed. However, at least in my case the problem seems not to be limited to 'when the window opens maximized'. Also (to Pedro): my initial description may have been confusing, but the problem is NOT related to a specific PDF file. As far as I can tell it happens with any file. It is therefore useless to attach a PDF file.