Non-unicode, user-defined chars not appear in Lyx editor since version 2.1.1

[Márton Payer]

Dear Developers & Users!

I'm a Windows user. Since the version of 2.1.1, probably due to the
transition to the new Qt version, my custom font, designed with
Fontforge, with several self-made character, not appear in the editor,
except, the original chars. And if I paste text e. g. from notepad,
after copy this text from Lyx and paste in an other textfile, the
self-made chars aren't in the pasted text. In other Windows notepads
and editors mostly this failure isn't exist (This error already exist
at Win 7, now I use Win 10). In my portable Lyx 2.1.1, in Win 10, this
error doesn't exist. If possible, I wish I could use a binary version
for install the latest versions too without this failure.

Thank you for your attention, Marton Payer, an everday user of Lyx