Dia Command Bar

A small extension that adds an Arc-style command bar to Dia. Demo below.

Why I made it

Arc had a feature I really liked: press ⌘T and a little bar shows up on top of whatever page you're on.

• one text box for your open tabs, bookmarks and history
• a few browser actions, and a normal search when nothing matches
• a Chromium extension, built for Dia and tested in plain Chromium
• no build step, no account, no runtime dependencies
• not an Arc clone: no spaces, no themes, no clever ranking

Try it

• this is the real interface on made-up data
• the four tabs are fake, so Enter just tells you what it would have done
• click inside it first so it picks up your keys

things to try

• type @ to see only tabs, or > to see the browser actions
• type a few letters of a tab name, like fig
• type github.com and it treats it as an address; type something with a space in it and it becomes a search
• press Ctrl+, (⌘, on a Mac) for settings. Under sources, switch on bookmarks and history and the sample ones will start showing up

new tab vs overlay

• the buttons above switch between the two ways it appears
• new tab is a full page with a clock; overlay floats over a website (the stripes stand in for the site)
• in overlay mode, Esc clears what you typed and a second Esc closes it
• Ctrl+Shift+L brings it back; drag the little handle at the top to move it

Using it

• on a website, press ⌘⇧L (Ctrl+Shift+L on Windows and Linux) or click the toolbar icon
• a fresh new tab gets the full-page version
• want ⌘T to work like Arc? There's a setting for it (see the rough parts)

• bookmarks and history are off until you switch them on, and the browser asks permission first
• results opened from the overlay go into a new tab by default, so the page you were reading stays put
• you can change that to replace the current tab

Settings

• seven sections: appearance, command bar, new tab, search, sources, overlay, shortcuts
• cosmetic: theme, accent color, font, spacing, corner roundness, width
• practical: search engine, how many results, where results open
• want the closest thing to Arc? The README lists the exact choices: blue accent, 14px corners, 620px wide, soft highlight, results in a new tab

Privacy and permissions

• no analytics, no remote scripts, no remote fonts
• the content security policy only allows one outside address, Google's autocomplete endpoint, and only if you turn suggestions on
• matching against tabs, bookmarks and history happens on your machine
• search suggestions are off by default. If you enable them, what you've typed so far (after three characters and a short pause) goes to Google, even if your search engine is something else
• addresses, @ * # > searches and private windows never send anything

Restore defaults in settings turns everything off again and revokes the optional permissions.

The rough parts

the ⌘T overlay is a workaround

• browsers don't let extensions take over ⌘T
• so the browser opens a new tab as usual, the extension waits for the bar to load on your previous page, switches back, and closes the empty tab
• you might see a quick flash while that happens
• it only ever closes the empty tab it was handed
• it spots a fresh tab by Dia's homepage address (chrome://start-page/ plus an id). Dia doesn't document that, so a future release could break it until I update

smaller things

• the overlay can't draw on chrome:// pages, the Chrome Web Store, or sites that refuse to be embedded. There it opens a regular tab instead
• on a new tab the browser sometimes keeps focus in its own address bar, so click the command bar or hit the shortcut
• it isn't on any extension store
• tested by running the real extension in an isolated Chromium profile with Playwright, plus unit tests for the timing cases in the new tab logic
• independent project, not affiliated with The Browser Company, Dia or Arc

Install

• the browser loads it straight from that folder, so don't move it afterwards
• changed something? hit reload on the extension card
• for ⌘T: settings → overlay → open new tabs as an overlay, then allow website access

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