Right clicking on the TRASH icon on my desktop produces a context menu with an "open in directory opus" selection / command.
However when I do that it opens TRASH in File Explorer
Other context menus seem to work as indicated
This is controlled by the options in Preferences / Launching Opus / Explorer Replacement. Set it to Replace Explorer for all folders to have the Recycle Bin opened in Opus as well.
I am using the USB version here at work. This option doesn't appear so I assume it's for the installed version only?
Parts of Explorer Replacement involve registry changes, so the portable version avoids anything to do with it by default.
You can turn on Explorer Replacement for portable versions via a .ini file. See Exporting to USB, near the bottom of the page.
This still doesn't work but I was only asking out of curiosity anyway, it's not a feature I use.