Open .phd files with Connect

Your users have been saving .phd files to their machines. But double-clicking one of them does nothing — no app is registered to open it. Connect's PWA file association fixes that: install Connect as an app, and .phd documents open from the file manager and land straight in a drive.

How it works

A Powerhouse document is a zip archive with a vendor MIME type — application/vnd.powerhouse.document+zip for .phd, application/vnd.powerhouse.document-model+zip for .phdm. Connect's web app manifest declares that it handles those two extensions, and when a user installs the PWA the browser registers the association with the operating system.

When the OS hands a file to Connect, the browser delivers it through the LaunchQueue API. Connect then shows the Open document dialog — pick a drive, import. Files opened this way travel the same path as drag-and-drop, so nothing about your document models or editors changes.

Supported platforms

File associations only work in Chromium-based browsers — Chrome, Edge, Brave. Firefox and Safari don't implement the File Handling API, so there's no association flow there at all; on those browsers users open documents by dragging a file into the Connect window.

Once Connect is installed as an app, per platform:

Platform	Behavior
Windows	.phd/.phdm register with the OS when the PWA is installed. Double-click opens Connect; right-click → Open with makes it the default.
macOS	Installing alone doesn't set the default app. Right-click a file → Get Info → Open with: → Connect → Change All…
Android	Open a .phd in the Files app and the app picker offers Connect.
Linux / ChromeOS	Chromium ships the feature, but how the association surfaces (open-with menus, .desktop entries) varies by distro and desktop environment — check the open-with dialog after installing.

Installing Connect as an app

1. Open your Connect URL in Chrome or Edge.
2. Click the install icon in the address bar — on desktop, the browser menu → Cast, save and share → Install page as app works too.
3. Done. The installed app now handles .phd and .phdm files.

The association belongs to the installed app, not to a browser tab: a user who only uses Connect as a web page will never get it.

What happens when you open a file

Double-click a .phd (or select several at once):

1. Connect launches — or, because launch_handler is focus-existing, an already-open window comes to the front and receives the files instead of a new window per file.
2. The Open document dialog lists each file and preselects the user's first drive; they can switch it.
3. Click Import — or Rename and import, when the drive already holds a document with the same name and the copy is automatically renamed to avoid it.

If the user has no drives yet, the dialog offers to create one first; the file stays queued and the dialog comes back once the drive exists.

Caveats

• Existing installs. The OS snapshots the file association at the moment the PWA is installed. If the association isn't live yet — or a later build adds a new file type — the browser picks it up on its own periodic manifest re-check; reinstalling the app is the sure fix.
• Desktop file-type icons. Chromium doesn't use per-type document icons on desktop yet (macOS synthesizes one from the app icon, and Windows support isn't implemented), so a .phd shows the OS's default icon for now.
• The import dialog, not a direct open. By design the association lands at the app root and asks for a destination drive — a manifest file handler can't dictate where inside the app a file opens, so the drive picker is as direct as the platform gets.

QuizA user on macOS wants to double-click .phd files and have them open in Connect. Which statement is true?

Deploying Connect yourself? The manifest is configurable — a package or the project can declare additional file types of its own. See Configure the PWA — File handling.