I know, this is probably an edge case, but there are still instances, where a user object tries to load data from session despite MW_NO_SESSION is set.
- MW 1.30 upwards
- Extension:CodeMirror on REL1_30 
- Extension:BootstrapComponents 
The case is reported on github  and only occours when Extensions CodeMirror and BootstrapComponents are installed.
What happens (roughly):
- while CodeMirror is active, BootstrapComponents is instanciated during a request to load.php: https://localhost/w/repo/load.php?lang=en&modules=startup&only=scripts&skin=vector&debug=true
- BootstrapComponents then tries to get the current skin from RequestContext
- this translages into an "illegal" call to User->loadFromSession()
Note, that this exception is only thrown in 1_30 upwards.
I fixed the exception in BootstrapComponents, so I don't need any help for that. Why do I report this:
- It feels unintuitive to check for MW_NO_SESSION only to get the current skin. But if this is the solution and "I" am the responsible party, please tell me
- I think, there is an underlying problem, but I can't pinpoint it
- I don't know, it this is important enough to follow up. If not, just close it.
relates to T127233