When I open Xcode it automatically opens the last projects that were open when it quit.
I have one .xcodeproj that gets displayed in red in the Project navigator and there are no files visible for the project. I am not able to compile the project.
Closing the window without quitting Xcode and re-opening it solves the issue and the project appears fine and I am able to compile.
I've scanned through the project.pbxproj file and nothing jumps out at me as an issue and it's quite strange when it works after re-opening the project.
I should also note that this happens on any machine that I clone the repo to.
Has anyone seen this before and somehow solved it?
I also get bothered by this problem for a long time(this comment is 2 years after your first post, for now, it's 2020-3-12).
A little different is, your project is red, mine is black but dim.
My workaround is hold alt/option and shift key, click icon of Xcode on dock, Xcode shows the welcome page, then double click the project.