Crash with the mcmeta reading of unicode font

Trying to edit 'unicode_page_04.png' and its meta, but getting an mcmeta reading error.
Tryed to change the encoding type (ANSI, UTF-8, UTF 8 without BOM) - without any changes.
Tryed to use x256 textures - unchanged (while my target is to make it x128)

Crash rep, .mcmeta and .png files applied.

[Maybe i'm doing it wrong or I've got into incomplete part of resourcepacks?]