[samples] Some PDF forms from the Canadian federal government do not show their contents, stuck at "Please wait..." asking to upgrade to Adobe Reader
On this page, I found some PDF forms to test with Okular, Papers and Evince running Poppler 23.08.0.
Many of those files work, but some of them don't.
When they don't work, they show a blank page with these contents:
Please wait...
If this message is not eventually replaced by the proper contents of the document, your PDF viewer may not be able to display this type of document.
You can upgrade to the latest version of Adobe Reader for Windows®, Mac, or Linux® by visiting http://www.adobe.com/go/reader_download.
For more assistance with Adobe Reader visit http://www.adobe.com/go/acrreader.
On top of that, Okular shows a prompt dialog, too:
Not all PDF forms from the canadian government trigger this behavior. Some of them load their contents fine, and can even be filled and saved, whether in Okular, Papers or Evince.
Here is a summary of which of those documents are able to display their contents, and which cannot:
Document's source | Works (contents show up)? | Attachment (for posterity) |
---|---|---|
IMM 5406E | No | imm5406e.pdf |
IMM 5475 | No | imm5475e.pdf |
IMM 5476 | Yes | imm5476e.pdf |
IMM 5409 | Yes | imm5409e.pdf |
IMM 5604 | Yes | imm5604e.pdf |
Mozilla/Firefox's PDFjs is able to open and render all of them, so maybe some part of their codebase might be useful as reference.
In this PDFjs ticket, I have discovered 9 other forms from the Canadian government that Poppler is unable to open, with the same symptoms. PDFjs is able to open them, although imperfectly, according to that linked ticket.