[LAU] [OT] Multi-monitor setup for extending and mirroring displays

Dear list, please excuse the following for being largely offtopic to linux audio. I can't seem to find any useful information via startpage.com nor can I think of a list I am subscribed to to ask the following: I sometimes have the need to show pdf slides in presentations and like using pdfpc[1], a "presenter console with multi-monitor support for PDF files" using an extended X display. I do as well have the need to show the (single) desktop I am working on. The only way I can achieve this is to switch back and forth between the two setups using xrandr. I am using a display manager (fluxbox) with multiple virtual desktops. I am wondering if there is a smarter less interrupting way. What if I had one extended display, whose left side is on my laptop's screen and right side on the video projector, and had something like a vnc-client on the right side, mirroring what is going on on the left side of the screen. I could then show what I am working on on the left screen but also have the pdf presenter console span the left and right side of this extended display together. I hope my description and question do make (some) sense. If anyone has an idea I'd be happy to know! thanks, and exuse the OT post, Peter [1] https://pdfpc.github.io/