Are cyrillic names not allowed as Page ID anymore?

Are Cyrillic names not allowed as Page ID anymore?
I wanted to modify existing page I made long time ago, and I can’t save it anymore.
It used to work before:

config:
  label: Климатизери
  order: "2"
  sidebar: true
blocks: []
masonry:

When I edited the display and wanted to save I got message:

"Page ID is only allowed to contain A-Z,a-z,0-9,_"