Hi Stephen

Sorry by frankness here, but when I look at df_material icons, I have the feeling that you guys were rushing to get the theme delivered in 19.1, and it got partially done.
The icons set are incomplete and not well proportionally sized, when compared with previous themes.

The chars mappings don't match with previous fonts, so S which previously was a printer, now does not exist in font used in df_material theme. in material font there in only one printer (colored) and its char code is 

Flat_touch/Desktop has 148 icons defined, while material has only 113.

The proportion of icon sizes in df_material are not good as well, when compared with df_flat icons.

Look at this 2 pictures:
Df_Flat_Icons when used with text.. Looks nice
Click image for larger version. 

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Df_Material icons, used with text .. Looks terrible:
Click image for larger version. 

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