zero width spaces no longer have zero width

[xfnw]

Describe the bug
in the latest release zero width space (U+200b), zero width non-joiner (U+200c), and zero width joiner (U+200d) now are displayed with the width of a normal space, instead of having no width

this breaks prompts and curses-like applications that expect zero width characters to have zero width

To Reproduce
Steps to reproduce the behavior:

1. type a zero width space with control+shift+u, typing 200b and hitting enter
2. the zero width space has width

Screenshots
broken behavior of the word test with a zero width space after the first letter:

how it should display:

Environment details
N/A

Additional context
reproducible with --config NONE.