[TonyTrapp]

SumatraPDF is my absolutely favourite PDF reader, but I wish the author took security more seriously. At least for a long while there were no official releases for months, if not years, with known crashes in muPDF (for which I think known exploits and patches existed), but since SumatraPDF used a custom muPDF version, it required manual patching. Maybe things are better these days (I see updates are more frequent again), but with PDFs being a big attack vectors these days, it leaves a bit of a sour aftertaste.