Certain (annotated) PDFs not opening
                    Report ID: 526606370
On Zotero 7.0.10 for Mac, certain PDFs which I have imported after annotating them on my Kindle Scribe are not opening properly. They open and display fine in Preview, on browsers, etc., but Zotero seems to not be seeing them as a proper PDF file.
Screenshot of the file not opening:
https://s3.amazonaws.com/zotero.org/images/forums/u10385439/8fy81idhpf3xht405ef9.png
Screenshot of the library pane:
https://s3.amazonaws.com/zotero.org/images/forums/u10385439/k4rve3mlf8n97zzguixv.png
Screenshot of the file open in Preview:
https://s3.amazonaws.com/zotero.org/images/forums/u10385439/1xp3ky8za2iaugu4w1tk.png
                
                            On Zotero 7.0.10 for Mac, certain PDFs which I have imported after annotating them on my Kindle Scribe are not opening properly. They open and display fine in Preview, on browsers, etc., but Zotero seems to not be seeing them as a proper PDF file.
Screenshot of the file not opening:
https://s3.amazonaws.com/zotero.org/images/forums/u10385439/8fy81idhpf3xht405ef9.png
Screenshot of the library pane:
https://s3.amazonaws.com/zotero.org/images/forums/u10385439/k4rve3mlf8n97zzguixv.png
Screenshot of the file open in Preview:
https://s3.amazonaws.com/zotero.org/images/forums/u10385439/1xp3ky8za2iaugu4w1tk.png
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https://drive.google.com/file/d/1bd7Qn9lqHNIhiqdBzA_nvGWgVJYDPv_M/view?usp=sharing
Although it opens fine in all the PDF viewers I tested, the file is still corrupted. I was able to fix it by going to File → Export and selecting the “Create PDF/A” option in Preview.
It would be good to report this issue to the PDF.js developers, but since the file isn’t freely available online, I’m unable to do so.