(Spyder-dev is here)
We will enable the reset spyder configuration method from the user interface in the next version (3.0.0).
In the meantime, you can reset open a terminal window (cmd in the Windows shell .. on Mac / Linux) and type
spyder --reset
If this still does not work, you can delete the .spyder folder in your user folder
Windows X:\Users\username\.spyder2\ (or X:\Users\username\.spyder\ )
Linux \home\username\.spyder2\ (or \home\username\.spyder\ )
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