Sumatra PDF is a PDF, ePub, MOBI, CHM, XPS, DjVu, CBZ, CBR reader for Windows

Released version 3.2

I am sorry to hear your installation resulted in loss of favourites, I had mentioned that this could be a problem during the development cycle, since I too was on occasion bitten by loss of customized files when repeatedly installing/uninstalling.

Many users may find that the previous SumatraPDF-settings.txt is often left behind in
%APPDATA%\SumatraPDF\ and if so you should be able to copy that across to
%LOCALAPPDATA%\SumatraPDF\ without any loss of favorites etc.

Cautionary advice to others

The correct procedure (which I don’t always follow) when uninstalling ANY software prior to a reinstallation is to back-up any customised files (in this case the advanced SumatraPDF-settings.txt, which will be renewed) then after installation replace the contents as required.

Thanks for your remarks. I just was curious about the circumstances and don’t mind the file size itself.

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Thank you for the update. I thought you would like to know that when I used Check for Update in the previous version, it incorrectly told me that I had the latest version.

It will normally tell you for the first week that you do have the latest (stable) version see

You may see that comments such as above in that first week(s) allows feedback of critical bugs and if necessary 3.2.1 can then be released without every user having to update twice in a short period.

Thank you for the response. I had missed that description of the release process.

Could you please make a separate version without debugging things? I’ve never had any issues with Sumatra PDF, so I don’t see any reason why I would need it. I’ll install that version and never bother you again =)

Thanks for the best PDF viewer!

Thank you for the update! I’ve checked a few times over the past few months, expecting a new release at any time, and lo-and-behold, here it is. Seems to be running great, thank you and keep up the good work.

Look inside version 0.2 (1.36 MB 2006-08-06) and every version since. You will see the word debug it is only the latest versions where the user can see and use the trigger to download the extra debugger files, simply ignore that option whilst there is no crash, however it is there when you need to report a problem.

It just looks like the developer accidentally released debug version of the project, just forgot to switch the build configuration from Debug to Release before building.

You can tell if it’s a full debug build it will say so in the top right corner and its potentially 50% larger than the coresponding normal release

@VEG: The Debug menu won’t show up in the next release build.

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I also noticed that size of the program is a few megabytes bigger now. It is not critical, just wonder what was added. I always advertise this program as extremely lightweight, and some people really care about it =)

Everyone says just add this small item like for example most recent was scalable SVG icons in place of the older bitmaps icons and also working with highlights & bookmarks, but they forget that needs lots of code to drive and control those small changes and items.
Byte for byte kjk has to weigh up size increase versus stability, new features etc.and often you may see him drop chunks of older code but the primary aim is compatibility which may involve alternative checks etc.

Both your request to “hide” the debug menu and today’s changes of adding several Italian translations had a nett effect of 0 bytes gain or loss in size
However, other changes mean that over the last 24 hours (5 changes) size has increased by roughly 1 KB

Without analysing every build, SumatraPDF potentially needs to double in size every few years, 10 years ago the best Adobe Acrobat Reader (v9 pdf or AI only for which I only use for 3D viewing) was about 100 MB, by 2014 v11 was about 400 MB, how much a full installation uses now I don’t care to know.

Much of the latest SumatraPDF 3.2 code changes were down to the newest MuPDF engine and if you look at the size of GUI less MuPDF-GL it is now over 35 MB (it does have a few extra features such as highlight editing and XFA form filling) However it also has lots less ability to handle multiple file types and is a pain to use for some basic reading tasks.

There are some good lightweight pdf only readers such as XpdfReader but that is about 24 MB (19 MB for x32 bit) using about 20 files

Thank you very much for your brilliant work!
I really appreciate this PDF viewer. All the settings and UI are my style.
Compared to other viewers, there is only one thing that I hope you add to this viewer if available. That is the permanent highlight or ink mark while reading the PDF.
Thank you again. Have a nice day!

Nothing is ever definite, however, there are potential unspecified changes to annotation in hand. How to edit a document in Sumatra PDF?

The Pre-release always has had temporary and permanent block highlighting, have you tried that?
If saved into the pdf they will be visible in any pdf viewer.

Just asking if there is any chance of an update on the horizon

There are multiple dailybuilds updates and regular bug fixed prerelease

However the “most robust” last month was still 3.1.2. and stable 3.2 is intended to be replaced by 3.2.1 as soon as practical.

I see that the treeview style has changed in Sumatra 3.2 to Vista style. I see arrows instead of +/- signs. I find this hard to visually understand. Is there an option to revert to tree view? I very much hate this new navigation pane style of tiny arrows.

Actually was changed last year to match current Windows Explorer style, as still used in Windows 10.

To me it’s not important when it was changed or whether it was done to match other Microsoft trends but if there is no option to revert to +/-, I would rather remain on the last version that had them, 3.1.2 forever.