Steps to reproduce:

1. open a Scintilla based editor (I've tested with Notepad++ and TeXnicCenter).
2. Write some text
3. Move navigator object to focus.
4. Start moving with Numpad 4 and 6 between words.

Expected behavior:

NVDA should report only words without spaces between them like in all other cases.

Actual behavior:

NVDA reports every space as a separate word.

System configuration:

NVDA version:
next-15133,1f3d46d2

NVDA Installed or portable:
Installed

Windows version:
Windows 8 x64

Name and version of other software in use when reproducing the issue:
Notepad++ v7.5.4 (64-bit), TeXnicCenter 2.02 Stable (64 bit)

Other questions:

Does the issue still occur after restarting your PC?
Yes
Have you tried any other versions of NVDA?
Yes from 2017,2 onward and it didn't work.