Hi mfedorov, thank you for posting!
According to our Spine documentation, "Single quotes may be used to surround key names (for example 'COMMA') or any typed character (for example ',' or ';') to cause the hotkey action to occur when that character is typed and to repeat after a delay if the key is held down. When using single quotes alt may be used but the modifiers ctrl and shift cannot be used."
The link to this page can be found below:
Spine Key Names