As versions go up, more bugs appear. Also, from Xcode 12, complete integration of macOS UI into UIKit started. When you are trying to debug on Xcode 12, you'll get to the most disturbing moment; no debug area in the Xcode. No bottom panel showing button. What you have to do is go to Menu > View > Debug Area > Show Debug Area ( Cmd + Shift + Y ). I don't know why they removed bottom panel button while right panel button is still there. Because there is no top-bottom split window scheme in iOS? C'mon, you can do better than that!
Also, there is a bug that randomly run button is disabled. You can still build/run by shortcuts. Only way to fix this is to completely restart Xcode.
