the cost of launching a new process with a gui is not cheap. there's a lot of setup before you even get a window up ... when that process is already there (terminal) with all of that cost paid for it is actually provably cheaper in terms of cpu cycles, latency etc. to pop up an image/video in your terminal. and cheaper not by 1 or 2 ms... but by 100's ms or more. that new window is not cheap. you also have the visual disconnect - the window pops up somewhere else with your wm having no idea that that new window is related to the terminal you ran it from because there will be no transient_for hints set to say that. relying on process tree hunting to figure this out is a crapshoot at best and will probably give you more misses than hits. we can go down that rabbit hole if you want but trust me - it is measurably less overhead to pop it up in a terminal with a few dozen chars worth of escapes sent to the terminal to do it.

In terms of wall clock time, on my system, it costs nothing. I can start a "Hello World" application based on Qt or GTK, and the window is there while I'm still releasing the Enter key. Technically, sure, a lot of things happen... But it's not happening on a P-90 anymore... :) BTW: My machine wasn't particularly strong or expensive either, when I bought it 6 years ago. ;)

When I read (in your other reply) that you are trying "soften the boundaries between workflows and bring some features of of workflow into another", well, that probably sounds nice... I just get a headache tbh...

I'm sure it was fun and a big achievement to implement that. And there obviously is a fan-base for that. So where am I... :)