Bookmark Launcher: Multi-Tab & Local File Support

The Goal

Open two URLs simultaneously in two tabs with one click, land on tab 1, and have it be searchable like a normal bookmark.

What Was Tried (and Why It Failed)

javascript: bookmark

Pasting javascript:window.open(...) as a bookmark URL — Chrome treated it as a search query and sent it to Google. Couldn't get it to save properly via the bookmarks bar dialog.

Local HTML file with window.open()

Created an HTML file that opens both URLs via script, bookmarked the file:/// path. It worked! But left an unwanted 3rd tab open — the HTML file itself.

window.close()

Added to the HTML file to close the launcher tab after opening the others. Chrome won't let a tab close itself if the user navigated to it directly (only works if the tab was opened by a script).

window.focus()

Tried to pull focus back to the current tab after window.open(). Chrome blocks this entirely for security reasons.

Various window.open + location.href orderings

Using location.href to navigate the current tab (so it becomes one of the two destinations) and window.open for the other. This avoids the extra tab problem, but Chrome always focuses the newly opened tab — no way to override this from a webpage context. Ended up on the wrong tab every time.

Why It Has to Be an Extension

A regular webpage (including a local HTML file) runs in a sandboxed context. Chrome deliberately blocks:

• window.focus() — can't steal focus
• Controlling which tab is active after window.open()
• Opening file:/// URLs from web context (cross-origin blocked)

A Chrome extension runs in a privileged context and has access to the chrome.tabs API, which allows:

.js

chrome.tabs.create({ url: 'https://site1.com', active: true });
chrome.tabs.create({ url: 'https://site2.com', active: false });

The active: false flag is the key — this is simply not possible from a webpage. Only extensions can do this.

Fixing the Extension

Problem 1: file:/// URLs not launching

Even with "Allow access to file URLs" toggled on in chrome://extensions, the extension may not be launching local file URLs. Likely a bug in how the extension calls chrome.tabs.create() with file:/// paths. Need to inspect the relevant code and verify the URL is being passed correctly.

Problem 2: Multi-tab bookmarks

Add support for a bookmark entry that contains multiple URLs. When launched, the extension:

1. Opens the first URL in a tab with active: true
2. Opens remaining URLs with active: false

This gives clean focus behavior that's impossible any other way.

Why This Will Be Cool

Multi-tab launching

Save a group of URLs as a single named bookmark. Search for it by name, click it, and all tabs open instantly — with focus on the right one. Way better than Chrome's Tab Groups (not searchable) or any HTML file hack.

Local file launching

Launch files on your computer directly from the bookmark launcher — open a local project, a reference doc, a design file. Anything with a file:/// path becomes a first-class bookmark.

Combined

A bookmark entry could open a local file and a web URL together — e.g. open your notes file alongside a reference site. Genuinely powerful for dev workflows.

Next Step

Share the extension code (specifically the URL-launching logic) to debug the file:/// issue and add multi-URL support.