UTF-8 Character Rendering Issue

[AlexBV117]

Describe the bug
I am in the process of switching over my terminal emulator from the default gnome terminal to kitty. However I am having an issue with getting a text banner from my neovim config to render properly. In gnome terminal it looks like the first screen shot (green). However cating out the exact same file in kitty (white) it looks very jagged.
I have tried changing my kitty.conf file to render the U+25E2,U+25E3,U+25E4, and U+25E5 characters differently but this hasn't fixed the issue. How can I get the triangle characters to print properly? I realise this is more a question than an issue but the help would be appreciated.

My current kitty.conf

vim:fileencoding=utf-8:foldmethod=marker

# Fonts
font_family      JetBrainsMono NFM Regular
bold_font        JetBrainsMonoNL NFM Bold
italic_font      JetBrainsMonoNL NFM Italic
bold_italic_font JetBrainsMonoNL NFM Bold Italic
font_size 12.0
disable_ligatures cursor

# Cursor
cursor #ededed
cursor_text_color #1a1b26
cursor_shape block
cursor_blink_interval 1
cursor_stop_blinking_after 0
shell_integration no-cursor

render_height U+25E5 20
render_height e29688 20

# Colour Theme (Tokyo Nighti)
include Tokyo_Night.conf

# Tap Bar
tab_bar_edge top
tab_bar_align left
tab_bar_style powerline
tab_powerline_style round

# Background
# background_image ~/.config/kitty/background.png
# background_image_layout cscaledi

# Advanced
wayland_titlebar_color background

# Keyboard Shortcuts

---

Screenshots

gnome terminal output

kitty's output

---

Environment details

kitty 0.31.0 created by Kovid Goyal
Linux mozhart 6.8.8-200.fc39.x86_64 #1 SMP PREEMPT_DYNAMIC Sat Apr 27 17:42:13 UTC 2024 x86_64
S
Kernel 6.8.8-200.fc39.x86_64 on an x86_64 (/dev/tty)

Running under: Wayland
Frozen: False
Paths:
  kitty: /usr/bin/kitty
  base dir: /usr/lib64/kitty
  extensions dir: /usr/lib64/kitty/kitty
  system shell: /bin/bash
Loaded config files:
  /home/sacha/.config/kitty/kitty.conf

Config options different from defaults:
bold_font                  JetBrainsMonoNL NFM Bold
bold_italic_font           JetBrainsMonoNL NFM Bold Italic
cursor_blink_interval      1.0
cursor_stop_blinking_after 0
disable_ligatures          1
font_family                JetBrainsMono NFM Regular
font_size                  12.0
italic_font                JetBrainsMonoNL NFM Italic
shell_integration          frozenset({'no-cursor'})
tab_bar_edge               1
tab_bar_style              powerline
tab_powerline_style        round
wayland_titlebar_color     1
Colors:
	active_border_color        #7aa2f7   
	active_tab_background      #7aa2f7   
	active_tab_foreground      #16161e   
	background                 #1a1b26   
	color0                     #15161e   
	color1                     #f7768e   
	color10                    #9ece6a   
	color11                    #e0af68   
	color12                    #7aa2f7   
	color13                    #bb9af7   
	color14                    #7dcfff   
	color15                    #c0caf5   
	color16                    #ff9e64   
	color17                    #db4b4b   
	color2                     #9ece6a   
	color3                     #e0af68   
	color4                     #7aa2f7   
	color5                     #bb9af7   
	color6                     #7dcfff   
	color7                     #a9b1d6   
	color8                     #414868   
	color9                     #f7768e   
	cursor                     #c0caf5   
	cursor_text_color          #1a1b26   
	foreground                 #c0caf5   
	inactive_border_color      #292e42   
	inactive_tab_background    #292e42   
	inactive_tab_foreground    #545c7e   
	selection_background       #283457   
	selection_foreground       #c0caf5   
	url_color                  #73daca   

Important environment variables seen by the kitty process:
	PATH                                /home/sacha/.local/bin:/home/sacha/bin:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin
	LANG                                en_GB.UTF-8
	EDITOR                              /usr/bin/nano
	SHELL                               /bin/bash
	DISPLAY                             :0
	WAYLAND_DISPLAY                     wayland-0
	USER                                sacha
	XDG_DATA_DIRS                       /home/sacha/.local/share/flatpak/exports/share:/var/lib/flatpak/exports/share:/usr/local/share/:/usr/share/
	XDG_RUNTIME_DIR                     /run/user/1000
	XDG_CURRENT_DESKTOP                 GNOME
	XDG_MENU_PREFIX                     gnome-
	XDG_SESSION_CLASS                   user
	XDG_SESSION_DESKTOP                 gnome
	XDG_SESSION_TYPE                    wayland

Additional context
I am running Fedora 39 and using JetBrainsMono NFM Regular as my font on both terminals.