Krzysztof Kowalczyk

First: thumbnails where? In Windows Explorer? Can you post screenshots: * before installing Sumatra * after installing Sumatra Are thumbnails generated by SumatraPDF showing up or not? There can be...

Clue: only happens with `-n` > 0 e.g. `-stress-test "C:\Users\kjk\OneDrive\!sumatra" *.epub -n 3` Could be related to: ``` __declspec(thread) static fz_context* fz_hb_secret = NULL; ``` which I patched to be...

Doesn't seem to happen for `.pdf` files so probably related to harfbuzz and multi-threading.

Maybe: ```diff diff --git a/src/SumatraPDF.cpp b/src/SumatraPDF.cpp index be3ef650a..261e2abf8 100644 --- a/src/SumatraPDF.cpp +++ b/src/SumatraPDF.cpp @@ -1286,10 +1286,16 @@ static void ReplaceDocumentInCurrentTab(LoadArgs* args, DocController* ctrl, Fil // cf. https://code.google.com/p/sumatrapdf/issues/detail?id=2541 // ReportIf(win->IsDocLoaded() &&...

Have you installed with admin privileges?

https://www.uscis.gov/i-130 is another form example. Some info at https://eclecticlight.co/2019/06/18/pdf-without-adobe-23-the-nightmare-of-forms/

To set number of columns we could have menu items with explicit numbers or add a modal dialog similar to `IDD_DIALOG_GOTO_PAGE` where user can enter number of columns. We would...

The combinations of view options and zoom levels is confusing already and will be even more. It would be good to design a modal dialog for setting those options in...

We also need to improve our render cache. At the very least significantly bump the number of cached pages because it was designed with assumption it only needs to keep...

Another thing: it seems in what is now non-continuous view it also makes sense to provide multiple rows, if the space is there. We also need to decide how to...