titlebar gets enabled when setting gtk-single-instance = true

[Quince-Pie]

current config:

background-opacity = 0.75

cursor-style = block
cursor-style-blink = false
shell-integration-features = no-cursor
gtk-single-instance = true
confirm-close-surface = false
window-decoration = none
gtk-titlebar = false
gtk-titlebar-hide-when-maximized = true

when I set gtk-single-instance = true the titlebar appears regardless of the config.
titlebar disappears as intended when setting it to false.

EDIT:
After trying different options it seems that gtk-single-instance = true was not the cause. But the titlebar seems to be dependent on
gtk-titlebar = false even when window-decoration is none or false.

window-decoration = none

shows the titlebar.

window-decoration = none
gtk-titlebar = false

removes the titlebar.

[jcollie]

Check and make sure that there are no additional copies of Ghostty running in the background. It may have an old copy of the config with the titlebar enabled.

[Quince-Pie]

Whoops, forgot about that while testing.

though it seems to rely on gtk-titlebar = false , commenting it shows the titlebar again.

which seems suspicious since the option reference mentions that gtk-titlebar:

This option does nothing when window-decoration is false or when running under macOS.

[rhodes-b]

What system are you on? (os, and Desktop Environment)