MetaPDF unresponsive on a long pdf

I am trying to access this 56 page pdf:

I am opening the PDF in Google Chrome. The page loads superfast, and I’m able to annotate first few pages. But, as soon as I get past the 12th page, MetaPDF becomes unresponsive. I can still open and work on the other tabs in Chrome, but can do nothing on MetaPDF page.

Do other people have the same problem? The PDF is publicly available so any one can test.


Thanks for reporting. I can in part reproduce on my machine, and we are looking into potential issues that might cause the heavy CPU load.

I had MetaPDF freeze on a 28 page document (I had it open in two tabs). This document worked just fine before I opened it in the second tab.

Is there anything we can do to provide debugging feedback to the developers when this happens?

If you could send the PDF file to, it would definitely help a lot in debugging.

problem is, it may work just fine on a document one time, and then become totally unresponsive next time. I do not know what is the trigger, that is why I was wondering if there is any debugging information we can provide to assist you in narrowing down the issue.

On my machine, I had to disable “Use hardware acceleration when available” in Google Chrome. After this, most PDFs worked fine in MetaPDF.

After the above setting, I was able to load this long PDF as well. Though navigating it was still problematic.

I have a Macbook and a Windows machine, and I have observed that using MetaPDF on Mac gives a much better experience than using it on Windows.

I have been facing difficulty using Chrome for a long time. Today after disabling 2 out of 5 plugins in chrome://plugins, my machine runs like a completely new machine. I was able to scroll smoothly until page 48 in the PDF that I have originally mentioned. Only after that, did the page become unresponsive.

Looks like there is still some problem with large PDF files, but, disabling the following 2 plugins has made the experience much much better:

  1. Adobe Flash Player
  2. Google Remote Desktop Viewer Plugin

I still have this problem - the Chrome tab with PDF opened in MetaPDF freezes, and I think it may be correlated with having multiple documents opened with MetaPDF. I only had Remote Desktop plugin, disabling it didn’t help. I cannot unfortunately share the PDFs - it is a paper I am reviewing.

I am unable to open the paper I need to review at all - scrolling freezes past the 3rd page of the document. I am really sorry to say this, but I had to switch to a different PDF annotator that seemingly has all the same features, except that it works just fine on this same document.

MetaPDF is in beta for a reason. The major goal of the beta is to find and fix problems like that.

If you can’t share the PDF perhaps you can give it a quick try to open it here:

That’s Mozilla’s PDF.js viewer on which MetaPDF is based. If it loads there we are optimistic to fix it eventually because it means it’s a MetaPDF problem and fully under our control. If you also have problems loading it there it’s a bit harder for us the fix but there is always the last resort reporting unresponsive PDFs to them.

We are currently refactoring the MetaPDF code and already removed some unnecessary complexity. We are definitely looking at these issues, but the tricky part is that they are very difficult to debug. It often seems to be a issue tied to a specific OS, browser, or even hardware setting.

yes, it works fine there. The initerface of that viewer looks very similar to Kami, and Kami works fine for that paper too.

Having a comparable problem, only with a PDF that’s only 5 pages long. It looks like a scanned document though, so maybe that’s part of the problem. Most of the time MetaPDF freezes a few seconds after the first page is loaded, one time I was able to scroll through the document but after I zoomed in so the text fitted my screen width it froze still. This doesn’t happen when I load the document in I’ve e-mailed the PDF to Andreas.

Thanks for providing the PDF file.

I am finding that metaPDF is quite slow in general but it is grinding to a standstill when I try to highlight text. I am not 100% certain it is the highlighting causing the slowdown or if that is coincidental. I get Chrome’s “Unresponsive page” box at some point whenever using metaPDF.

In this instance the document is 15 pages and the file is 2MB.

I can appreciate that it is very difficult to diagnose these issues without a lot more detail on the specific context - is there a way of producing log files that may be helpful to you in diagnosis?

The only comparison I’ve got is that I can open the same document and annotate it in PDF-Xchange and Xodo.

As neither of those automatically sync changes with Google Drive, relying on manual saves, I turned ‘Auto-save’ off in metaPDF case that was the cause of the problem. metaPDF became more responsive initially, but it was still much slower, stuttered and eventually resulted in the “Unresponsive page” message.

Many thanks.

I just wanted to report a similar issue with a relatively small pdf- ten pages long. On my laptop, there is considerable resource use with the fan kicking in. On my desktop, it also ultimately gets sluggish by the time I get to the fifth page and I end up having to close the unresponsive tab.

I hope you guys get to fix this; metapdf is otherwise great to work with and is a great compliment to paperpile, which just became my favorite citation manager after ten years of using Zotero (and I have tried every citation manager out there at some point in time during those ten years)

I love this app. I’m also experiencing slowness on this file:

I noticed that when I checked off material acceleration in chromium parameters, the file would totally jam (i.e. stop responding beyond my patience). With material acceleration ON, the scrolling and highlighting is just very slow. It happens on a few files to different degrees.

I am also having this issue on multiple files, many of which are less than 12 pages in length. I’ve sent one document via email.
Please do you best to sort this! I love this application, but my my dissertation cannot happen with these obstacles.

Hi, I have similar problem with multiple PDFs.
here is one of them which I need to reload after 2-3 minutes everytime to be clickable !