Is there a way to right-click a photo and get the “Open With” prompt while running a portable DEV build (5.9) (WD_Black external HDD)? I’m thinking ENV variables might do the trick - but wouldn’t that require a local installation on the Windows drive as well.
Yes. Right click the file, then “open with” and then “choose another app”. Scroll down until you see “more apps”. Click that. Then scroll down again until you see “find another app on this PC”. Click that, and navigate to the exe file for rawtherapee. Then select it, and that’s it!
@RUNLEVEL3 I haven’t used Windows in many years, but I seem to recall that this same right-clicked menu that @bkv notes might also provide an option box you can check to make Rawtherapee your default app for opening other files with the same extension?
Perhaps that feature is buried in Windows system preference setting cluster, but I’m sure it’s in there somewhere. That is, if you’d like to avoid having to continue specifying RT as your associated app with a particular file type, e.g., your RAW files.