How can I remove this space from glyphs in my prompt?

[embeddedpenguin]

I've highlighted (in purple) the space to the left of os_icon.

I've tried setting
typeset -g POWERLEVEL9K_PROMPT_CHAR_LEFT_{LEFT,RIGHT}_WHITESPACE=false. Setting this doesn't seem to affect anything.

[romkatv]

This looks like a bug in the terminal. It may go away if you switch to the recommended font.

[embeddedpenguin]

This looks like a bug in the terminal. It may go away if you switch to the recommended font.

That did solve the issue, thanks!