[X] VimDevIcons is the last loaded vim plugin?
[X] What version of vim are you using?
nvim v0.4.3
[X] Are you using Mac, Linux or Windows?
Pop-OS
[X] Provide screenshots where appropriate

Having the same issue, also in Pop OS. However most icons show up besides js file extensions for some reason and all other fonts besides "Hack" font make my text in terminal look weird.
Having the same issue, All icons appear well just JavaScript icon.
Hmm can you verify that the correct font is being used?
Please refer to https://github.com/ryanoasis/vim-devicons/wiki/FAQ-&-Troubleshooting#why-isnt-it-working-how-come-i-dont-see-any-icons to see if it's any help.
Ensure that you're using a NERD patched font.
~/.fontsfc-cache -fvWorked for me in Ubuntu but when I installed Pop OS, I got the same issue. Did you solve the problem?
Solved it by using alacritty as my terminal. Configured to use Monaco Nerd Font on the ~/.config/alacritty/alacritty.yml file.
# Font configuration
font:
# Normal (roman) font face
normal:
family: "Monaco Nerd Font"
style: Regular
Not sure why Monaco Nerd Font is not showing as option in gnome-terminal
Hello :wave:
I am just getting started with VIM and NerdTree. I would like to have these dev icons, but I do not want to change my color scheme's font.
I'm using the gruvbox color scheme. If I install additional fonts, wouldn't that affect my gruvbox color scheme?
Right now, this is what I see:

You need to patch your font or probably it's already here. The important thing is, you need to have a Nerd patched font.
Most helpful comment
Having the same issue, also in Pop OS. However most icons show up besides js file extensions for some reason and all other fonts besides "Hack" font make my text in terminal look weird.