What happens on my computer, is that OBS creates two windows on the single OBS icon(one for the OBS the program, and another for the fullscreen projector, because I am projecting to a screen) so if I'm on another app and I want to go straight back to OBS, when I click OBS on the taskbar, it doesn't go straight into OBS, it makes me select between entering the OBS app or the Fullscreen projector.
I'm never going to need to click on the Fullscreen projector, because all I need is to project the image, that additional window created is useless. I want to eliminate it and have OBS, the application, open right away when I click it on the taskbar, which is only possible if there is a single OBS window open, so I'm not forced to make an additional selection regarding which OBS window I specifically want to open when I click OBS on the taskbar. I do need OBS to project to my second screen, but I don't really need it to open a separate fullscreen projector window on my taskbar for that.
The worship program I use had the same thing (it created a window icon in the task bar just for the projector) but I found a setting to remove that, so it wouldn't add an unnecessary window to the program, while of course still projecting the image.
Not sure if I am making any sense...