Quick fix:

Save this into a file ("dontdrag.py" or whatever you like). From Poser Menu use "File -> Run Python Script" and point to the file you saved.

from __future__ import print_function

for p in poser.WxAuiManager().GetAllPanes():
    p.Movable(False).Dockable(True).Dock().Floatable(False)

print("Done.")

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