Crash in Suffixes.glyphsPalette

[schriftgestalt]

Details:
Traceback (most recent call last):

File "vanillaEditText.py", line 15, in controlTextDidEndEditing_
self.action_(notification.object())

File "vanillaBase.py", line 514, in action_
self.callback(sender)

File "plugin.py", line 90, in editTextCallback
self.changeDotSuffix( editText.get(), i )

File "plugin.py", line 61, in changeDotSuffix
glyph.name = newName

File "GlyphsApp/GlyphsApp/__init__.py", line 6660, in <lambda>

File "GlyphsApp/GlyphsApp/__init__.py", line 6657, in GSGlyph_setName

NameError: The glyph name ".ssty" already exists in the font.

App:3.1.1-3139