When in a folder where the user does not have write permission, the 'create new' option in the context menu is disabled. - Open another folder where the user has write permission in a new tab - Switch to the new tab - Open the context menu. The 'create new' option remains disabled.
Confirmed, thanks for the report. Workaround: press F5.
I cannot reproduce. I recall someone fixing this but I can't find the commit right now.
I can still reproduce this with KDE Neon running today's git master.
It seems that now the Create New option is never disabled, and an error is shown if the user doesn't have permission. Marking as fixed.