To explain a bit; Whenever the Compile button disappears, this means that something in the compilation caused the editor to become unlinked from the code. This means that the attempt that broke this link and any subsequent attempts while the editor is open, will not update the editor as the editor is working off the last working .dll. That’s why this usually happens with failed builds rather than successful ones.
Could you provide your edited .build.cs file(s) to see if I can get the same behavior? It does seem like it would be correct in this case about the module not being properly set up but I can’t tell without seeing it.