Bug with the Preview on the right side of Xcode

Hey there,

i hope this is the right place to ask my question. I have a very strang bug on Xcode. When i open my bug-free code file with Xcode 9.4.1 i dont have the preview show on the right side (the thing where i can see my variables that i declared). But when i open the file with Xcode Beta it works. I searched through the internet and so many people had this issue arround a year ago (at this it was a bug from the program the guys told me), but do i have this now and how du i fix it?

Greetings

Luca

This is the forum about Swift language, not Xcode. To submit your bug report, please, visit Bug Reporting - Apple Developer.