Using Firefox as the WebApp Browser in Omarchy - Solution / Tutorial

[pi-hackr]

Hi everyone!

I wanted to share a setup I’ve been using to replace Chromium with Firefox for Omarchy WebApps. This allows me to use a dedicated Firefox profile for WebApps while keeping all Omarchy keybindings and .desktop integrations intact, and gives the added benefit of a minimal, distraction-free UI with tabs, address bar, and toolbars hidden, making WebApps feel more like standalone applications.

1. Modify omarchy-launch-webapp script

The script is usually located at:

~/.local/share/omarchy/bin/omarchy-launch-webapp

Here’s a modified version that redirects WebApp calls to Firefox:

#!/bin/bash

# Redirect standard WebApp calls to Firefox WebApp profile
browser=$(xdg-settings get default-web-browser)

case $browser in
firefox* )
    # Launch Firefox directly with the dedicated WebApp profile
    exec setsid uwsm app -- firefox --no-remote -P "WebApps" --new-window --class WebApp "$1" "${@:2}"
    ;;
*)
    # Old Chromium fallback for other browsers if needed
    browser="chromium.desktop"
    exec setsid uwsm app -- $(sed -n 's/^Exec=\([^ ]*\).*/\1/p' {~/.local,~/.nix-profile,/usr}/share/applications/$browser 2>/dev/null | head -1) --app="$1" "${@:2}"
    ;;
esac

Notes:

• --new-window ensures each WebApp opens in its own window.
• -P "WebApps" specifies the dedicated WebApp profile.
  • This part can be omitted if you don’t need a minimal UI. In that case, you can also skip the next steps (profile creation and CSS).
• --no-remote allows multiple Firefox instances.
• --class WebApp allows custom Hyprland rules for window placement and behavior.
• Existing Omarchy keybindings and .desktop files still work without modification.
• The script will still work even if you revert your default browser back to Chromium.
• Important: Changes in ~/.local/share/omarchy/bin/omarchy-launch-webapp may be overwritten during Omarchy updates, so you’ll need to reapply them after updating (at least until this is part of the official releas ;) ).

2. Create a dedicated WebApp profile

If you want a minimal UI for your WebApps, create a Firefox profile:

firefox -P "WebApps" -CreateProfile "WebApps"

• This creates a separate profile called WebApps.
• You can configure userChrome.css and other settings independently.
• You can use Firefox Sync to share history, add-ons, bookmarks, and passwords between your normal profile and the WebApp profile if you want a unified experience.

3. Firefox WebApp Minimal UI (CSS)

Create or edit userChrome.css in the WebApp profile directory (~/.mozilla/firefox/<profile_folder>/chrome/userChrome.css) to hide UI elements:

/* ---- Firefox WebApp Minimal Mode ---- */

/* Hide tabs, address bar, bookmarks, menu bar, status bar, sidebar */
#TabsToolbar,
#nav-bar,
#PersonalToolbar,
#statuspanel,
#sidebar-box {
  visibility: collapse !important;
}

/* Hide title bar (optional for a cleaner window) */
#titlebar {
  visibility: collapse !important;
}

/* Menu bar appears when ALT or F10 is pressed */
:root[sizemode="normal"] #toolbar-menubar {
  visibility: collapse !important;
}
#toolbar-menubar[autohide="false"] {
  visibility: visible !important;
}

Notes:

• for applying the changes you need to enable the custom stylesheets preference in the new profile. Go to about:config in the WebApp profile and set: toolkit.legacyUserProfileCustomizations.stylesheets = true
• This makes Firefox WebApp windows minimal, while still allowing temporary access to the menu bar with Alt or F10.

4. Benefits of this setup

• Full Omarchy integration without changing keybindings or .default files.
• All WebApps run in a separate Firefox profile (WebApps) if desired, or you can use your normal profile.
• Minimal UI for a true app-like experience.
• Optional: Combine with Hyprland window rules for floating, sizing, and centering.
• You can share browsing history, add-ons, bookmarks, and passwords with your main profile via Firefox Sync.
• Works regardless of the default browser, so reverting your default back to Chromium won’t break WebApps.

If anyone has ideas on further improving this setup, I’d love to discuss them!

[thatonehen]

you're like, a great person

[thatonehen]

i could not figure this out

[iliyan03]

I was just wondering how to do this. Great guide! Many thanks

[xdmx]

Awesome one, thank you for sharing it. The only thing I've noticed is that when I get the dialog for some permissions (location, video/audio, notification, etc) it flickers and I can't interact with it. When I disable the custom style it works, so it seems something related to it. I don't know if it's just me / my machine or others are having the same issue.

[kacperkrolak]

I had the same issue, and I've had a much better experience after replacing my userChrome.css with this file:

https://github.com/MrOtherGuy/firefox-csshacks/blob/master/chrome/autohide_toolbox.css

[codyjgeorge]

I feel like I missed something somewhere. I installed the firefox dev edition. Its extracted in downloads currently. I typed the command in step 2 but it says bash: command not found: firefox however I cd'd into .mozilla/firefox and i can see files there. Did I not install correctly?

I also tried opening firefox dev edition from downloads and setting it as default and still no luck. Can someone point me in the right direction please?

[iliyan03]

Hey, I'm pretty new to Linux, but I'll try to help. The shell can't find the firefox executable because it's directory isn't on your PATH. You can create a symlink to the firefox executable in a directory that is on your PATH, such as /usr/local/bin:
sudo ln -s ~/Downloads/firefox-145.0b6/firefox/firefox /usr/local/bin/firefox
You may need to change the path to your executable, but in my case it's this. Then you can execute the command mentioned in step 2. You should be be able to run firefox from anywhere.

[codyjgeorge]

Awesome! I'll try this out tonight and see if I can get it working. Thank you! I'll let you know how it goes.

[codyjgeorge]

@iliyan03 I was able to get it working. Thank you for the insight, that fixed my issue and helped me get everything figured out.

[iliyan03]

Glad to hear that!

[Docmos]

Works perfectly. Thanks a lot!

[mnkll]

Did the same but in a separate launch command so updates don't screw me over, and for Firefox fork Zen with Zen Internet Extension for some extra eye candy. Thanks for the userChrome @pi-hackr, spared me some debugging, maybe at some point I'll post the write up, for now the TLDR command order.

This requires the Zen Internet Extension and Zen Mod to be active on your main profile though (or you set them up regularly in GUI for the WEBAPP profile manually):

cat > ~/.local/share/omarchy/bin/omarchy-launch-webapp-zen <<'EOF'
#!/bin/bash
exec setsid uwsm app -- zen-browser --no-remote -P "WebApp" --new-window --class WebApp "$1" "${@:2}"
EOF

chmod +x ~/.local/share/omarchy/bin/omarchy-launch-webapp-zen

echo 'unbind = SUPER SHIFT, A' >> ~/.config/hypr/bindings.conf
echo 'bindd = SUPER SHIFT, A, ChatGPT, exec, omarchy-launch-webapp-zen "https://chatgpt.com"' >> ~/.config/hypr/bindings.conf

zen-browser -P "WebApp" -CreateProfile "WebApp"
WEBAPP_PROFILE=$(find ~/.zen -maxdepth 1 -type d -name '*.WebApp' | head -n 1)
DEFAULT_PROFILE=$(find ~/.zen -maxdepth 1 -type d -name '*.Default*' | head -n 1)

cp -r "$DEFAULT_PROFILE/"* "$WEBAPP_PROFILE/" 2>/dev/null || true
mkdir -p "$WEBAPP_PROFILE/chrome"

cat >> "$WEBAPP_PROFILE/user.js" <<'EOF'
user_pref("toolkit.legacyUserProfileCustomizations.stylesheets", true);
user_pref("browser.tabs.closeWindowWithLastTab", true);
user_pref("browser.sessionstore.resume_session_once", true);
user_pref("browser.fullscreen.autohide", true);
user_pref("mod.sameerasw_zen_compact_sidebar_type", "0");
user_pref("zen.view.compact.enable-at-startup", true);
user_pref("zen.welcome-screen.seen", true);
user_pref("zen.widget.linux.transparency", true);
user_pref("ui.systemUsesDarkTheme", 1);
EOF

cat >> "$WEBAPP_PROFILE/chrome/userChrome.css" <<'EOF'
#TabsToolbar,
#nav-bar,
#PersonalToolbar,
#statuspanel,
#sidebar-box {
  visibility: collapse !important;
}
#titlebar {
  visibility: collapse !important;
}
:root[sizemode="normal"] #toolbar-menubar {
  visibility: collapse !important;
}
#toolbar-menubar[autohide="false"] {
  visibility: visible !important;
}
EOF

[grepex]

Thanks for this! Could you elaborate on what Zen Mod needs to be installed?

[dharmavagabond]

You don't need to install any mod, however, the one mentioned is this one: https://sameerasw.com/zen

[mnkll]

Yup, that's the one, its 2 fold a mod and an extension. However, @dharmavagabond is correct that you do not need any of them, it's just eye candy.

[dakshcs]

thanks so much!!

[opajanvv]

Awesome! I just added a link this to page in my blog post about replacing Chromium by Firefox.

[little-burrito]

Hello! I'm not at my computer, so I haven't tested this myself, but I think running in kiosk mode might be a nice experience.

Just add the -kiosk argument when opening Firefox.

https://support.mozilla.org/en-US/kb/firefox-enterprise-kiosk-mode

[NoahzArkk]

this is awesome, you're awesome man thanks so much!

[4by3]

For me using --class WebApp didn't work however --name WebApp seems to work fine