Getting images with dual displays on linux

I'm using SikulixIDE v2.0.5 on a CentOS7 operating system. When I try to take a screenshot using the icon in the IDE, here's what happens on a dual monitor setup-- the images on my primary display are mirrored onto my secondary display and anything that was on my secondary display is hidden. I can then take a screenshot of the mirrored desktop on my secondary display only. In other words, I can only take a screenshots on my secondary monitor of windows displayed on my primary. Taking screenshots technically "works" but it's a little funky.

Questions about dual monitor support have been asked before, but many of them are now over a decade old. I'm wondering what the current status is of dual monitor support on Linux. Are there any user-facing options that I can use to maybe straighten this out? I'll settle with only a single display being supported as long as it's the same display for everything.