[fontInfoView] BlueValues lost when number of values is odd

[arialcrime]

In Robofont Version 4.1b (build 2110061420) I encountered the following problem which according to @typemytype might be related to the functionality of fontInfoView (or how Robofont interacts with it).

Steps to reproduce

In a new font: Open Font Info, go to the Postscript sheet and enter 2 values into BlueValues. Hit okay. Go back to the Postscript Sheet and add a third value (one shouldn’t, I know) and click okay again. Open the Postscript sheet in the font info another time and all BlueValues entries are gone.

[typemytype]

a NumberSequenceFormatter marks the input as invalid is its uneven so the EditText returns None.

I dont know if it should return a invalid string.