No widescreen in SC:R

I just installed SC:R on a new computer after a long hiatus (1 or 2 years). When I had it installed on my previous computer, I’m sure I remember playing it in widescreen (16:9 aspect ratio). However, now I can only play it in 4:3 aspect ratio whether I select Windowed, Windowed Fullscreen, or Fullscreen. There also doesn’t seem to be a difference between Windowed Fullscreen and Fullscreen. How do I get widescreen back?

Have you purchased the Remastered upgrade? Or are you playing the base (free) version?

I purchased the Remastered upgrade (to go along with my original copy of Starcraft from 1998 and Brood War). I was able to figure it out tonight. I had to go to Window mode, then drag the window out to resize it. It eventually asked if I’d like to reset the window. When it reset the window, it started working in fullscreen). Thanks!