I just switched to elementary yesterday and I absolutely love it. There's a problem, though.
When I go on Twitter in Firefox, my profile picture (https://pbs.twimg.com/profile_images/819743601831841794/5k22sTXF_400x400.jpg) appears purple instead of blue. The weird thing is that my cover photo, which uses the same blue (https://pbs.twimg.com/profile_banners/477405869/1484277064) is perfectly fine. There's obviously some issue with image compression or something.
Either way, both images appeared to be the same blue in Firefox in Xubuntu and Windows, so the color issue lies with elementary.
If I tilt my laptop backward, the blues match again.
I poked around in the system settings' color panel, but I don't see anything that could help me. I even installed the GNOME Color Profile Viewer, but I don't know how to use it and I'm afraid I'll mess something up if I mess around with the settings.
How do I fix/calibrate my screen colors?