This is one of the most infuriating things Apple has ever done to me. I have my spaces set up exactly how I want them. STOP RUINING THEM! Took me longer than I'd like to admit to find this little check box.

Oh yeah that's the fucking worst, I forgot about that setting. I know illustrator was on the 15th space just fucking leave it.

I am changing this right now.

Thank you! You saved me from going crazy, did not know about that checkbox.

as someone who has not yet worked with apple, what is this?

@jebediah when you switch between workspaces and full screen applications. Default is that the arrangement of the apps is sorted after frequently used, not your preference. Un-tick box and they will be arranged after your preference.

Had no idea this was occurring, thanks!