4K smooth support- PDFs

Brass Contributor

First post here, don't know if it's already been mentioned here but has 4K support for PDFs been discussed here before? Context: PDFs rendered in 4K resolution lag immensely (regardless of size) when opened with Edge Chromium. I suspect this is because unlike Edge Legacy, Edge Chromium renders the entire PDF from the start (you can try it out yourself and zoom out max + fast scroll below and you'll see everything already loaded) while Edge Legacy only rendered the page you're in and load the rest when you scroll to that page (a bit slow when browsing pages fast, but thanks to this feature, PDFs in 4K work wonders with 0 lag everywhere). A quick solution for this would be to have an edge://flag or setting to turn off rendering the entire PDF at once and instead load it per page (or pages) while viewing said page. This would be favorable for those that don't lag in 2K resolution, 4K users to experience no lag, and also help Edge's devs to make a quick solution for this so they work on other things and not take time on this. Another possible solution would be to set specific resolution for PDFs but I don't know how easy it is to implement this. Hopefully a fix for laggy PDFs on 4K comes soon as I've been using Edge Legacy for PDFs and Edge Chromium for browsing (both open at the same time) which only generate extra battery drain. Thanks for reading :)

14 Replies

@OmegaMalkior Thanks for the detailed post, and welcome to our community!

That's a really neat and unique suggestion; I'll get in touch with the PDF team and pass this on to them.


Fawkes (they/them)
Project & Community Manager - Microsoft Edge

Thank you for the welcome and thanks for your support! Very excited to be able to use Edge Chromium as my only browser for both web browsing and PDFs :)

P.S. forgot to mention that PDFs are also laggy on lower resolutions than 4K (have my Surface Pro 5 with native 2736 x 1824 and it experiences the same issues 4K resolutions does to a slightly lesser extent) which for students using a Surface line product it would be a hit if it were fixed for them too :)

Thanks again and cheers!
i think this is problems from chromium IMHO. microsfot just realese edge chromy this year and promises fix smoth scrolling as well, a problem that google don't care. all we have to do is wait rn

@OmegaMalkior thanks for reporting this issue. Happy to inform that our team is already working on improving PDF scrolling in the new Microsoft Edge to make it as good as it was in legacy Edge. Please expect some improvements in upcoming releases.

And yes, the problem is the same on all monitors but may get aggravated on 4K monitors. I hope this helps. 

Thank you all so much for your team effort to making the absolute perfect browser :) cannot wait!

@OmegaMalkior Of course, we're happy to help. And we also really appreciate all of the excitement and feedback! :)


Fawkes (they/them)
Project & Community Manager - Microsoft Edge

@Deleted So excited to know that the team is working on fixing this issue! Can't wait for it! Is there any estimate of when the update will come? This summer? This Autumn? Maybe Winter? :lol:


Nonetheless, I don't want my excitement to put too much pressure on the team! After all, the final product has to be polished! Great job! :happyface:

Still no improvement. Please fix this. Cant properly use the browser this way with my MICROSOFT surface pro 6...

Unfortunately there is still no improvement and it's almost October 2020. Hope the Microsoft team will work on this issue soon. I have paid pricey for surface pro 6 and this is not appreciated.

best response
Microsoft Verified Best Answer

@AleksMKD @OmegaMalkior @Deleted - We have introduced scrolling improvements in Microsoft Edge version 86 which is currently in Beta!! Do try it out and let us know if it improves the scrolling experience for you.

@posinha The scrolling experience is definitely better! It is smoother. However, it seems to have a major tradeoff. When scrolling, the document is white and takes a moment to load. It is fast to load but slow enough to hinder visual searching. I think it needs a significantly better content loading to be considered a smooth experience, as it makes a lot harder to search for specific points in the document.

@TofuLynx Thanks for the feedback! We're working to make the scroll experience even better and address the white page rendering issue that you're talking about.

@OmegaMalkior I think one of the reasons that it did it so well was because Legacy Edge let windows do all the hard work, which is why the touchscreen scrolling isn't as good as it was in the last version. Edge probably used windows code that allowed it to prioritize tasks to maximize the frame rate, usually at 60 fps. Even when the frame rate slowed, Edge and Explorer managed to animate things smoothly regardless of how the browser was doing by (I assume) letting windows have control of that task. Trade secrets I assume.


Microsoft said they wont add the code, or whatever sorcery they have to new edge because it has to run on more operating systems than just windows. I'm not sure why they don't just add it exclusively for the windows version and say that it works slightly better on windows, but they have their reasons.