🖥 The projector overlay

The projector overlay is the window you put on the board: the class chat floats on top, and whatever you load fills the screen behind it. Everything here runs in your own browser, which is exactly why private files and local files work so well.

Feeding chomp.0

chomp.0 is the hungry chomper plant idling on an empty overlay, and he is also the loader. Three ways to feed him:

• Drop a link or a file anywhere on the screen. He rises the moment a drag crosses the window.
• Paste a link.
• Click him for the feed menu: a Google Drive picker, a "This computer" file button, and a paste-any-link box.

One browser rule: a tab itself won't drag in. Drag the padlock (or sliders) icon from the address bar instead, or copy the address and paste it.

Pasting while something is already on screen doesn't yank it away: the new link joins the playlist instead. Dropping a link on the screen always swaps right away: that is the deliberate hand-off.

What he eats

• Google Slides, Docs, Sheets, Forms, and Drive files (videos, PDFs, images). Ordinary share or edit links are fine: chomp.0 converts them to the embeddable form himself.
• YouTube (including Shorts), Vimeo, and Twitch channels, videos, and clips.
• Direct links to PDFs, images (png, jpg, gif, webp, avif, svg), video (mp4, webm, mov), and audio (mp3, wav, m4a, ogg).
• Most sites that allow embedding: Wikipedia, Desmos, GeoGebra, PhET, and many more.
• GitHub code files. GitHub refuses to load inside other apps, so the overlay fetches the file's raw text and paints it as a big, readable code panel with an "Open on GitHub" link. The panel lives on your screen only; use the mirror to show it on student devices.

Local files never upload

Files from your computer (PDFs, images, video, audio) display straight from your machine and never upload anywhere. Office slide decks need one step first: export as PDF, or upload to Google Slides, and feed him that.

Private Google files just work

Students never load this screen; only your browser fetches the media. So a private deck, Doc, Sheet, or Drive file works as long as the Google account signed in on your browser can open it. No publish-to-web, no changing sharing settings.

The playlist

Preload a whole period before the bell. Open 📚 Playlist in the toolbar, then paste links (with an optional name each), browse Drive with 🔷, or add a file from this computer with 📂. During class, the ◀ ▶ arrows step through in order; inside the panel you can reorder rows, rename them, or play any row directly.

The playlist is saved per class, on that device: period 3's list waits for period 3. Files chomp.0 eats stay in it automatically, with limits (3 file slots, 25 MB each, on that computer only, oldest makes way).

To reuse a playlist elsewhere, give it a name (✏️ next to the title) and use ☁️ Save: it lands in your Drive's teachChat › Playlists folder, and 📥 From Drive loads it in another class. ⬇️ and 📁 export and import a plain file as an offline fallback. Only links travel; local files stay planted where they were fed.

When a site refuses to embed

Some sites tell every browser "never show me inside another app." That is their setting, not yours, and teachChat checks for it on every load, so you get an honest explanation instead of a dead "refused to connect" panel. The big streaming services (Netflix, Hulu, Disney+, Max, Peacock, Prime) block every app this way through DRM.

The workaround: open that site full screen, then use 🪟 Float on top (under 🛠 More) to pop the chat into an always-on-top window (Chrome and Edge) that stays above full-screen apps. More rescues live in Troubleshooting.

The live mirror

For students who can't see the board, 🪞 Mirror to student devices (under 🛠 More) puts the board on their own screens. They get still snapshots about once per second, with no audio: perfect for slides and annotations, useless for movies, on purpose.

Pick a source: this teachChat screen (chomp.0's media plus the chat, so it covers code panels and local files too) or any other tab, window, or screen via the browser's picker. Stop any time with 🪞 Stop mirror in the toolbar or the browser's own stop-sharing bar.

Showing a local file to the class's devices: feed it to chomp.0 first, then mirror this teachChat screen.