Arc Windows to Firefox

Reworked and streamlined for Firefox 137+

• Still working on every platform! Windows, Linux and macOS
• Based on current Firefox vertical tabs & sidebar system. (Plus Firefox is working on locally-processed Link Preview and sidebar show on hover!)
• Refined layout compared to past ArcWTF version. Popup URL bar is enabled by default.
• Plus: Now that tab group is available natively, I can provide closer "folder" styling to Arc.
• Plus: You can utilize the Firefox sidebar for "tab splitting" using extensions like Page Sidebar.
• No need to setup Sidebery or Userchrome Toggle, all recommended extensions would be optional.
• Tradeoff: No Spaces. There's no tree-group tabs system. Still no URL bar on the left. (Install Zen! I've made some mods and worked on its documentations.)

Screenshots

• Hidden sidebar mode

• Expanded sidebar mode

• "Split view" with Page Sidebar extension

• 9 folder colors available to choose

Theme components to download (for now)

• "icons", "folder-icons", and "content" folder
• userChrome.css, popup.css, tabgroups.css, and userContent.css
• Background-0.png and Background-1.png for new tab background
• Arc.ico if you want to apply the icon in your Windows taskbar

Applying the theme

• Install latest Firefox, enable Vertical Tabs via right click menu or in Settings
• Download the repo () and extract it on your Firefox profile directory (Get the path in about:profile. Create the "chrome" folder if you haven't)
• Make sure these boolean prefs in about:config are enabled/"true":
  • toolkit.legacyUserProfileCustomizations.stylesheets to enable user custom styling
  • svg.context-properties.content.enabled to enable SVG coloring based on theme.
• Right click toolbar > enter Customize Toolbar mode, move the buttons like this.
• Open the tab sidebar and adjust the length as needed. Also install some supporting extensions below if you want

Supporting extensions (optional)

1. Use "Split View" in sidebar by using one of these extensions (I already mod the icons!)

• Page Sidebar by Stevan VD
• Sidebar Tab by Shailendra
• Side Browser by Tukapiyo

2. "Popup window" by Ett Chung or Maxfocus to simulate Peek
3. Adaptive Tab Bar Color by Eason Wang if you like adaptive colors based on websites
4. or automaticDark by Simon KH Zhang if you prefer to switch between two specific dark/light themes.

Some optional external tweaks

1. Replace Firefox icon on Windows Start Menu and Taskbar

   Download Arc.ico, open C:\ProgramData\Microsoft\Windows\Start Menu\Programs directory, right click Firefox shorcut, click 'Properties', click 'Change Icon...' and use the ICO file for maximum Arc feel. Pin to taskbar too.

2. Use Segoe UI Variable (Windows 11 default font) as Firefox UI font. Download from CufonFonts.

   Add this to your userChrome.css: * {font-family: "Segoe UI Variable Display" !important;}

TODOs

• Splitting the userChrome file
• Working on refining the "Tabs on the right" mode
• Making the browser padding gap customizable as variable
• Streamlining context menu options to make it closer to Arc while still maintaining functionality for Firefox
• Transparency support (External help needed, if you've cracked transparency for your OS, reach me out or send a PR!)
• and more...

CREDITs

• Concept & specific icons from The Browser Company
• Fluent icons from Microsoft
• Fluent icons implementation and menu spacing from bmFtZQ - edge-frfox
• Folder icons from ferrocyante - Arc-H
• Better unloaded tabs styling from Felkazz' Zen Mods collection
• Javisperez on SVGRepo - base of sidebar & split tabs icons
• Past guidance from MrOtherGuy
• Compact extensions menu (past version) from DatGuyPiko

FF theme recommendations (2024)

• Nord Polar, Nord Dark
• Arc Dark Theme, Arc Theme
• Activist - Soft
• Foto - Bold
• Plum Torte
• Dark Teal (chrome-like)

FF theme recommendations (2025) - coming soon

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