This is also occurring on Chrome, which has the same print dialog UI as GX, but not Edge, which has a different UI for the print dialog altogether.
Basically, when printing a pdf file from the browser (either online or local file), there is no option for the orientation, whereas for some reason it's there for regular web pages, along with margins and different scale options. The preview usually recognizes whether the pages are in landscape or portrait, and yet the printout is in portrait whether you like it or not. This is especially annoying when printing landscape presentation slides or documents with mixed landscape/portrait pages into OneNote. This is not a problem of the "Print to OneNote" virtual printer since it works just fine with Edge and pdf viewer desktop programs, which do have the orientation option and even automatically and correctly differentiate between portrait and landscape pages in mixed-page documents. Indeed, the option in GX and Chrome is missing no matter which printer you select.
Sure there's the "regular way" of doing it like opening with a pdf reader app but when printing dozens of files per day, the extra steps of "navigating to and opening file folder, waiting for pdf reader to open, print, then close all of them again" get very tedious compared to just "click download notification which auto opens new tab, print, done".
I just don't understand how such a basic option like choosing between portrait and landscape is missing when so many other more complicated features are available.
I'm on Windows 11, Opera GX LVL4 (core: 91.0.4516.95), everything is up to date and yes, I've tried disabling all extensions, reset settings, tried on another browser, etc.
I don't need personal tech support, I just wish this was fixed.