Steps to reproduce:

1. Load a PDF document with 0 pages

2. Enter some text in the search textbox and click the next/prev buttons

Expected: the search textbox should be either disabled or should ignore any search operation

Actual: an error occurs

Workaround:

    Private Sub pdf_Viewer_DocumentLoaded(sender As Object, e As EventArgs)
        If pdf_Viewer.Document.Pages.Count = 0 Then
            pdf_Toolbar.SearchTextBox.Enabled = False
            pdf_Toolbar.NextButton.Enabled = False
            pdf_Toolbar.PreviousButton.Enabled = False
        Else
            pdf_Toolbar.SearchTextBox.Enabled = True
            pdf_Toolbar.NextButton.Enabled = True
            pdf_Toolbar.PreviousButton.Enabled = True
        End If
    End Sub

The attached file lorem-ipsum.pdf is rendered incorrectly in PdfViewer. I suspect it has something to do with kerning, because monospace font is not affected. Adobe Acrobat, Foxit PDF Reader, and Chrome render the file correctly.

The file was created with Pandoc, open source software, converting a markdown file (.md) to .pdf.